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5-Day Uncertainty Track last updated Mon, 01 Sep 2025 20:41:54 GMT


Wind Speed Probabilities last updated Mon, 01 Sep 2025 20:41:54 GMT

Issued at 1100 AM HST Mon Sep 01 2025 000 WTPZ41 KNHC 012040 TCDEP1 Tropical Storm Kiko Discussion Number 7 NWS National Hurricane Center Miami FL EP112025 1100 AM HST Mon Sep 01 2025 Kiko continues to gradually become better organized on conventional satellite imagery with increasingly impressive curved banding noted in 1-minute GOES-18 imagery. The latest subjective Dvorak estimates range from 55-65 kt while objective intensity estimates from UW-CIMSS continue to be in the 45-50 kt range. Based on a blend of the data and improving appearance on satellite imagery over the last few hours, the initial intensity is increased to 55 kt for this advisory. Kiko has been moving toward the west-southwest at a slightly slower speed, with an estimated motion of 255/6 kt. A strengthening subtropical ridge to Kiko's north should cause this general motion to continue for the next day or so. After that time, Kiko should turn back toward the west due to its position due south of the strongest part of the ridge. By the end of the forecast period, a west-northwestward motion is likely as Kiko starts to reach the southwestern portion of the ridge's influence. There is very large along-track spread in the guidance, meaning that there is high uncertainty in Kiko's forward speed. The latest guidance has trended slower. The NHC forecast is slower and a bit to the north of the previous forecast, but not as slow as most of the latest consensus models. This latest track forecast is fairly close to the 12Z ECMWF model. Relatively warm ocean temperatures and light wind shear should allow Kiko to steadily strengthen over the next couple of days. If Kiko were to move south of the NHC forecast track, it could encounter stronger shear in 1-2 days, as the models show stronger upper level winds south of about 13N latitude. The other factor that complicates the intensity forecast is the possibility that some dry air tries to entrain into the circulation. The peak forecast intensity has been increased a bit to show a peak of 95 kt in 60-72 hours. This is closer to the latest HCCA and high resolution hurricane models, some of which bring Kiko to major hurricane intensity. Late in the forecast period, some slight weakening is possible due to slightly cooler ocean temperatures and the potential for slightly drier and more stable air. The intensity forecast lies near the upper end of the guidance envelope. FORECAST POSITIONS AND MAX WINDS INIT 01/2100Z 13.8N 126.7W 55 KT 65 MPH 12H 02/0600Z 13.7N 127.7W 65 KT 75 MPH 24H 02/1800Z 13.6N 128.9W 75 KT 85 MPH 36H 03/0600Z 13.6N 130.3W 85 KT 100 MPH 48H 03/1800Z 13.6N 131.7W 90 KT 105 MPH 60H 04/0600Z 13.8N 133.2W 95 KT 110 MPH 72H 04/1800Z 13.9N 134.8W 95 KT 110 MPH 96H 05/1800Z 14.3N 138.1W 85 KT 100 MPH 120H 06/1800Z 15.2N 141.6W 85 KT 100 MPH $$ Forecaster Hagen

Issued at 2100 UTC MON SEP 01 2025 000 FOPZ11 KNHC 012039 PWSEP1 TROPICAL STORM KIKO WIND SPEED PROBABILITIES NUMBER 7 NWS NATIONAL HURRICANE CENTER MIAMI FL EP112025 2100 UTC MON SEP 01 2025 AT 2100Z THE CENTER OF TROPICAL STORM KIKO WAS LOCATED NEAR LATITUDE 13.8 NORTH...LONGITUDE 126.7 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 55 KTS...65 MPH...100 KM/H. Z INDICATES COORDINATED UNIVERSAL TIME (GREENWICH) PACIFIC DAYLIGHT TIME (PDT)...SUBTRACT 7 HOURS FROM Z TIME HAWAIIAN STANDARD TIME (HST)...SUBTRACT 10 HOURS FROM Z TIME WIND SPEED PROBABILITY TABLE FOR SPECIFIC LOCATIONS CHANCES OF SUSTAINED (1-MINUTE AVERAGE) WIND SPEEDS OF AT LEAST ...34 KT (39 MPH... 63 KM/H)... ...50 KT (58 MPH... 93 KM/H)... ...64 KT (74 MPH...119 KM/H)... FOR LOCATIONS AND TIME PERIODS DURING THE NEXT 5 DAYS PROBABILITIES FOR LOCATIONS ARE GIVEN AS OP(CP) WHERE OP IS THE PROBABILITY OF THE EVENT BEGINNING DURING AN INDIVIDUAL TIME PERIOD (ONSET PROBABILITY) (CP) IS THE PROBABILITY OF THE EVENT OCCURRING BETWEEN 18Z MON AND THE FORECAST HOUR (CUMULATIVE PROBABILITY) PROBABILITIES ARE GIVEN IN PERCENT X INDICATES PROBABILITIES LESS THAN 1 PERCENT PROBABILITIES FOR 34 KT AND 50 KT ARE SHOWN AT A GIVEN LOCATION WHEN THE 5-DAY CUMULATIVE PROBABILITY IS AT LEAST 3 PERCENT. PROBABILITIES FOR 34...50...64 KT SHOWN WHEN THE 5-DAY 64-KT CUMULATIVE PROBABILITY IS AT LEAST 1 PERCENT. - - - - WIND SPEED PROBABILITIES FOR SELECTED LOCATIONS - - - - FROM FROM FROM FROM FROM FROM FROM TIME 18Z MON 06Z TUE 18Z TUE 06Z WED 18Z WED 18Z THU 18Z FRI PERIODS TO TO TO TO TO TO TO 06Z TUE 18Z TUE 06Z WED 18Z WED 18Z THU 18Z FRI 18Z SAT FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT 10N 130W 34 X 1( 1) 2( 3) 2( 5) 2( 7) X( 7) X( 7) 15N 130W 34 X 10(10) 41(51) 6(57) 3(60) X(60) X(60) 15N 130W 50 X 1( 1) 11(12) 4(16) X(16) X(16) X(16) 15N 130W 64 X X( X) 4( 4) 1( 5) X( 5) X( 5) X( 5) 10N 135W 34 X X( X) X( X) 1( 1) 7( 8) 3(11) X(11) 15N 135W 34 X X( X) 2( 2) 5( 7) 67(74) 10(84) X(84) 15N 135W 50 X X( X) X( X) 1( 1) 37(38) 12(50) X(50) 15N 135W 64 X X( X) X( X) X( X) 19(19) 9(28) X(28) 10N 140W 34 X X( X) X( X) X( X) X( X) 4( 4) 3( 7) 15N 140W 34 X X( X) X( X) X( X) 1( 1) 39(40) 34(74) 15N 140W 50 X X( X) X( X) X( X) X( X) 15(15) 26(41) 15N 140W 64 X X( X) X( X) X( X) X( X) 6( 6) 16(22) 20N 140W 34 X X( X) X( X) X( X) X( X) 1( 1) 5( 6) 15N 145W 34 X X( X) X( X) X( X) X( X) 1( 1) 15(16) 15N 145W 50 X X( X) X( X) X( X) X( X) X( X) 3( 3) 15N 145W 64 X X( X) X( X) X( X) X( X) X( X) 1( 1) 20N 145W 34 X X( X) X( X) X( X) X( X) X( X) 5( 5) $$ FORECASTER HAGEN

Issued at 1100 AM HST Mon Sep 01 2025 000 WTPZ31 KNHC 012039 TCPEP1 BULLETIN Tropical Storm Kiko Advisory Number 7 NWS National Hurricane Center Miami FL EP112025 1100 AM HST Mon Sep 01 2025 ...KIKO CONTINUES TO STRENGTHEN... SUMMARY OF 1100 AM HST...2100 UTC...INFORMATION ----------------------------------------------- LOCATION...13.8N 126.7W ABOUT 1265 MI...2035 KM WSW OF THE SOUTHERN TIP OF BAJA CALIFORNIA MAXIMUM SUSTAINED WINDS...65 MPH...100 KM/H PRESENT MOVEMENT...WSW OR 255 DEGREES AT 7 MPH...11 KM/H MINIMUM CENTRAL PRESSURE...999 MB...29.50 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 1100 AM HST (2100 UTC), the center of Tropical Storm Kiko was located near latitude 13.8 North, longitude 126.7 West. Kiko is moving toward the west-southwest near 7 mph (11 km/h) and this motion is expected to continue through tonight, followed by a turn back toward the west on Tuesday. Maximum sustained winds have increased to near 65 mph (100 km/h) with higher gusts. Steady strengthening is forecast during the next couple of days, and Kiko is expected to become a hurricane by tonight. Tropical-storm-force winds extend outward up to 45 miles (75 km) from the center. The estimated minimum central pressure is 999 mb (29.50 inches). HAZARDS AFFECTING LAND ---------------------- None. NEXT ADVISORY ------------- Next complete advisory at 500 PM HST. $$ Forecaster Hagen

...KIKO CONTINUES TO STRENGTHEN... As of 11:00 AM HST Mon Sep 01 the center of Kiko was located near 13.8, -126.7 with movement WSW at 7 mph. The minimum central pressure was 999 mb with maximum sustained winds of about 65 mph.

Issued at 2100 UTC MON SEP 01 2025 000 WTPZ21 KNHC 012038 TCMEP1 TROPICAL STORM KIKO FORECAST/ADVISORY NUMBER 7 NWS NATIONAL HURRICANE CENTER MIAMI FL EP112025 2100 UTC MON SEP 01 2025 TROPICAL STORM CENTER LOCATED NEAR 13.8N 126.7W AT 01/2100Z POSITION ACCURATE WITHIN 30 NM PRESENT MOVEMENT TOWARD THE WEST-SOUTHWEST OR 255 DEGREES AT 6 KT ESTIMATED MINIMUM CENTRAL PRESSURE 999 MB MAX SUSTAINED WINDS 55 KT WITH GUSTS TO 65 KT. 50 KT....... 20NE 0SE 0SW 0NW. 34 KT....... 40NE 30SE 20SW 40NW. 4 M SEAS.... 45NE 0SE 0SW 45NW. WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT. REPEAT...CENTER LOCATED NEAR 13.8N 126.7W AT 01/2100Z AT 01/1800Z CENTER WAS LOCATED NEAR 13.8N 126.4W FORECAST VALID 02/0600Z 13.7N 127.7W MAX WIND 65 KT...GUSTS 80 KT. 64 KT... 10NE 0SE 0SW 0NW. 50 KT... 20NE 0SE 0SW 20NW. 34 KT... 50NE 40SE 30SW 50NW. FORECAST VALID 02/1800Z 13.6N 128.9W MAX WIND 75 KT...GUSTS 90 KT. 64 KT... 15NE 0SE 0SW 10NW. 50 KT... 30NE 20SE 20SW 30NW. 34 KT... 50NE 50SE 40SW 50NW. FORECAST VALID 03/0600Z 13.6N 130.3W MAX WIND 85 KT...GUSTS 105 KT. 64 KT... 15NE 10SE 0SW 10NW. 50 KT... 30NE 20SE 20SW 30NW. 34 KT... 60NE 50SE 40SW 50NW. FORECAST VALID 03/1800Z 13.6N 131.7W MAX WIND 90 KT...GUSTS 110 KT. 64 KT... 15NE 15SE 10SW 15NW. 50 KT... 30NE 30SE 20SW 30NW. 34 KT... 60NE 60SE 40SW 60NW. FORECAST VALID 04/0600Z 13.8N 133.2W MAX WIND 95 KT...GUSTS 115 KT. 64 KT... 15NE 15SE 10SW 15NW. 50 KT... 30NE 30SE 20SW 30NW. 34 KT... 60NE 60SE 50SW 60NW. FORECAST VALID 04/1800Z 13.9N 134.8W MAX WIND 95 KT...GUSTS 115 KT. 64 KT... 15NE 15SE 10SW 15NW. 50 KT... 30NE 30SE 20SW 30NW. 34 KT... 60NE 60SE 50SW 60NW. EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 100 NM ON DAY 4 AND 125 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY OUTLOOK VALID 05/1800Z 14.3N 138.1W MAX WIND 85 KT...GUSTS 105 KT. 50 KT... 30NE 30SE 20SW 30NW. 34 KT... 60NE 60SE 50SW 60NW. OUTLOOK VALID 06/1800Z 15.2N 141.6W MAX WIND 85 KT...GUSTS 105 KT. 50 KT... 30NE 30SE 20SW 30NW. 34 KT... 70NE 60SE 40SW 60NW. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 13.8N 126.7W NEXT ADVISORY AT 02/0300Z $$ FORECASTER HAGEN

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0233 PM CDT Mon Sep 01 2025 Valid 012000Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SOUTHERN KANSAS TO NORTHWEST OKLAHOMA... ...SUMMARY... Isolated severe thunderstorms may occur across parts of southern Kansas and western/northern Oklahoma this afternoon and evening, with isolated large hail and damaging winds the main threats. ...20z Update... The previous forecast remains on track with only minor adjustments made to reflect recent convective trends. Initial thunderstorm development along a weak surface front is noted from northeast to southwest KS as of 19 UTC. Based on regional VWPs, mid-level flow remains relatively strongest across southern to southwest KS on the west/southwest side of the upper wave, which should promote a slightly higher potential for severe gusts and/or hail this afternoon/evening. The Marginal risk area was slightly adjusted to better capture this potential. See MCD #2025 for additional short-term details. Elsewhere, only minor adjustments to the thunder line were needed. An occasional lightning flash or two will be possible during the 09-12 UTC period across central CA, but recent guidance continues to suggest that lightning coverage/probability will likely remain below 10%. ..Moore.. 09/01/2025 .PREV DISCUSSION... /ISSUED 1122 AM CDT Mon Sep 01 2025/ ...Southern/Central Plains... A mid-level shortwave trough centered over eastern NE late this morning will move southeastward toward the southern Plains and Ozarks by tonight. This will occur in association with a belt of modestly enhanced north-northwesterly mid-level winds (around 30-40 kt at 500 mb). While the related surface response will remain muted, a weak surface front/wind shift will progress southward from KS into OK, with a relatively moist air mass preceding the advancing boundary. Ongoing low clouds/stratus should continue to gradually erode this afternoon, yielding ample insolation and a corridor of moderate instability and steepening low-level lapse rates, particularly across southern KS into northwest OK. Widely scattered thunderstorm development is probable by mid/late afternoon near the front/wind shift as the boundary layer warms. The enhanced north-northwesterly flow aloft will contribute to 30-40 kt of effective bulk shear, which should support multicell clusters and perhaps marginal supercells. Isolated severe hail/damaging winds will be possible through early evening as storms develop southward from parts of southern KS into western/northern OK. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0233 PM CDT Mon Sep 01 2025 Valid 012000Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SOUTHERN KANSAS TO NORTHWEST OKLAHOMA... ...SUMMARY... Isolated severe thunderstorms may occur across parts of southern Kansas and western/northern Oklahoma this afternoon and evening, with isolated large hail and damaging winds the main threats. ...20z Update... The previous forecast remains on track with only minor adjustments made to reflect recent convective trends. Initial thunderstorm development along a weak surface front is noted from northeast to southwest KS as of 19 UTC. Based on regional VWPs, mid-level flow remains relatively strongest across southern to southwest KS on the west/southwest side of the upper wave, which should promote a slightly higher potential for severe gusts and/or hail this afternoon/evening. The Marginal risk area was slightly adjusted to better capture this potential. See MCD #2025 for additional short-term details. Elsewhere, only minor adjustments to the thunder line were needed. An occasional lightning flash or two will be possible during the 09-12 UTC period across central CA, but recent guidance continues to suggest that lightning coverage/probability will likely remain below 10%. ..Moore.. 09/01/2025 .PREV DISCUSSION... /ISSUED 1122 AM CDT Mon Sep 01 2025/ ...Southern/Central Plains... A mid-level shortwave trough centered over eastern NE late this morning will move southeastward toward the southern Plains and Ozarks by tonight. This will occur in association with a belt of modestly enhanced north-northwesterly mid-level winds (around 30-40 kt at 500 mb). While the related surface response will remain muted, a weak surface front/wind shift will progress southward from KS into OK, with a relatively moist air mass preceding the advancing boundary. Ongoing low clouds/stratus should continue to gradually erode this afternoon, yielding ample insolation and a corridor of moderate instability and steepening low-level lapse rates, particularly across southern KS into northwest OK. Widely scattered thunderstorm development is probable by mid/late afternoon near the front/wind shift as the boundary layer warms. The enhanced north-northwesterly flow aloft will contribute to 30-40 kt of effective bulk shear, which should support multicell clusters and perhaps marginal supercells. Isolated severe hail/damaging winds will be possible through early evening as storms develop southward from parts of southern KS into western/northern OK. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0233 PM CDT Mon Sep 01 2025 Valid 012000Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SOUTHERN KANSAS TO NORTHWEST OKLAHOMA... ...SUMMARY... Isolated severe thunderstorms may occur across parts of southern Kansas and western/northern Oklahoma this afternoon and evening, with isolated large hail and damaging winds the main threats. ...20z Update... The previous forecast remains on track with only minor adjustments made to reflect recent convective trends. Initial thunderstorm development along a weak surface front is noted from northeast to southwest KS as of 19 UTC. Based on regional VWPs, mid-level flow remains relatively strongest across southern to southwest KS on the west/southwest side of the upper wave, which should promote a slightly higher potential for severe gusts and/or hail this afternoon/evening. The Marginal risk area was slightly adjusted to better capture this potential. See MCD #2025 for additional short-term details. Elsewhere, only minor adjustments to the thunder line were needed. An occasional lightning flash or two will be possible during the 09-12 UTC period across central CA, but recent guidance continues to suggest that lightning coverage/probability will likely remain below 10%. ..Moore.. 09/01/2025 .PREV DISCUSSION... /ISSUED 1122 AM CDT Mon Sep 01 2025/ ...Southern/Central Plains... A mid-level shortwave trough centered over eastern NE late this morning will move southeastward toward the southern Plains and Ozarks by tonight. This will occur in association with a belt of modestly enhanced north-northwesterly mid-level winds (around 30-40 kt at 500 mb). While the related surface response will remain muted, a weak surface front/wind shift will progress southward from KS into OK, with a relatively moist air mass preceding the advancing boundary. Ongoing low clouds/stratus should continue to gradually erode this afternoon, yielding ample insolation and a corridor of moderate instability and steepening low-level lapse rates, particularly across southern KS into northwest OK. Widely scattered thunderstorm development is probable by mid/late afternoon near the front/wind shift as the boundary layer warms. The enhanced north-northwesterly flow aloft will contribute to 30-40 kt of effective bulk shear, which should support multicell clusters and perhaps marginal supercells. Isolated severe hail/damaging winds will be possible through early evening as storms develop southward from parts of southern KS into western/northern OK. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0233 PM CDT Mon Sep 01 2025 Valid 012000Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SOUTHERN KANSAS TO NORTHWEST OKLAHOMA... ...SUMMARY... Isolated severe thunderstorms may occur across parts of southern Kansas and western/northern Oklahoma this afternoon and evening, with isolated large hail and damaging winds the main threats. ...20z Update... The previous forecast remains on track with only minor adjustments made to reflect recent convective trends. Initial thunderstorm development along a weak surface front is noted from northeast to southwest KS as of 19 UTC. Based on regional VWPs, mid-level flow remains relatively strongest across southern to southwest KS on the west/southwest side of the upper wave, which should promote a slightly higher potential for severe gusts and/or hail this afternoon/evening. The Marginal risk area was slightly adjusted to better capture this potential. See MCD #2025 for additional short-term details. Elsewhere, only minor adjustments to the thunder line were needed. An occasional lightning flash or two will be possible during the 09-12 UTC period across central CA, but recent guidance continues to suggest that lightning coverage/probability will likely remain below 10%. ..Moore.. 09/01/2025 .PREV DISCUSSION... /ISSUED 1122 AM CDT Mon Sep 01 2025/ ...Southern/Central Plains... A mid-level shortwave trough centered over eastern NE late this morning will move southeastward toward the southern Plains and Ozarks by tonight. This will occur in association with a belt of modestly enhanced north-northwesterly mid-level winds (around 30-40 kt at 500 mb). While the related surface response will remain muted, a weak surface front/wind shift will progress southward from KS into OK, with a relatively moist air mass preceding the advancing boundary. Ongoing low clouds/stratus should continue to gradually erode this afternoon, yielding ample insolation and a corridor of moderate instability and steepening low-level lapse rates, particularly across southern KS into northwest OK. Widely scattered thunderstorm development is probable by mid/late afternoon near the front/wind shift as the boundary layer warms. The enhanced north-northwesterly flow aloft will contribute to 30-40 kt of effective bulk shear, which should support multicell clusters and perhaps marginal supercells. Isolated severe hail/damaging winds will be possible through early evening as storms develop southward from parts of southern KS into western/northern OK. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0233 PM CDT Mon Sep 01 2025 Valid 012000Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SOUTHERN KANSAS TO NORTHWEST OKLAHOMA... ...SUMMARY... Isolated severe thunderstorms may occur across parts of southern Kansas and western/northern Oklahoma this afternoon and evening, with isolated large hail and damaging winds the main threats. ...20z Update... The previous forecast remains on track with only minor adjustments made to reflect recent convective trends. Initial thunderstorm development along a weak surface front is noted from northeast to southwest KS as of 19 UTC. Based on regional VWPs, mid-level flow remains relatively strongest across southern to southwest KS on the west/southwest side of the upper wave, which should promote a slightly higher potential for severe gusts and/or hail this afternoon/evening. The Marginal risk area was slightly adjusted to better capture this potential. See MCD #2025 for additional short-term details. Elsewhere, only minor adjustments to the thunder line were needed. An occasional lightning flash or two will be possible during the 09-12 UTC period across central CA, but recent guidance continues to suggest that lightning coverage/probability will likely remain below 10%. ..Moore.. 09/01/2025 .PREV DISCUSSION... /ISSUED 1122 AM CDT Mon Sep 01 2025/ ...Southern/Central Plains... A mid-level shortwave trough centered over eastern NE late this morning will move southeastward toward the southern Plains and Ozarks by tonight. This will occur in association with a belt of modestly enhanced north-northwesterly mid-level winds (around 30-40 kt at 500 mb). While the related surface response will remain muted, a weak surface front/wind shift will progress southward from KS into OK, with a relatively moist air mass preceding the advancing boundary. Ongoing low clouds/stratus should continue to gradually erode this afternoon, yielding ample insolation and a corridor of moderate instability and steepening low-level lapse rates, particularly across southern KS into northwest OK. Widely scattered thunderstorm development is probable by mid/late afternoon near the front/wind shift as the boundary layer warms. The enhanced north-northwesterly flow aloft will contribute to 30-40 kt of effective bulk shear, which should support multicell clusters and perhaps marginal supercells. Isolated severe hail/damaging winds will be possible through early evening as storms develop southward from parts of southern KS into western/northern OK. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0233 PM CDT Mon Sep 01 2025 Valid 012000Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SOUTHERN KANSAS TO NORTHWEST OKLAHOMA... ...SUMMARY... Isolated severe thunderstorms may occur across parts of southern Kansas and western/northern Oklahoma this afternoon and evening, with isolated large hail and damaging winds the main threats. ...20z Update... The previous forecast remains on track with only minor adjustments made to reflect recent convective trends. Initial thunderstorm development along a weak surface front is noted from northeast to southwest KS as of 19 UTC. Based on regional VWPs, mid-level flow remains relatively strongest across southern to southwest KS on the west/southwest side of the upper wave, which should promote a slightly higher potential for severe gusts and/or hail this afternoon/evening. The Marginal risk area was slightly adjusted to better capture this potential. See MCD #2025 for additional short-term details. Elsewhere, only minor adjustments to the thunder line were needed. An occasional lightning flash or two will be possible during the 09-12 UTC period across central CA, but recent guidance continues to suggest that lightning coverage/probability will likely remain below 10%. ..Moore.. 09/01/2025 .PREV DISCUSSION... /ISSUED 1122 AM CDT Mon Sep 01 2025/ ...Southern/Central Plains... A mid-level shortwave trough centered over eastern NE late this morning will move southeastward toward the southern Plains and Ozarks by tonight. This will occur in association with a belt of modestly enhanced north-northwesterly mid-level winds (around 30-40 kt at 500 mb). While the related surface response will remain muted, a weak surface front/wind shift will progress southward from KS into OK, with a relatively moist air mass preceding the advancing boundary. Ongoing low clouds/stratus should continue to gradually erode this afternoon, yielding ample insolation and a corridor of moderate instability and steepening low-level lapse rates, particularly across southern KS into northwest OK. Widely scattered thunderstorm development is probable by mid/late afternoon near the front/wind shift as the boundary layer warms. The enhanced north-northwesterly flow aloft will contribute to 30-40 kt of effective bulk shear, which should support multicell clusters and perhaps marginal supercells. Isolated severe hail/damaging winds will be possible through early evening as storms develop southward from parts of southern KS into western/northern OK. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0233 PM CDT Mon Sep 01 2025 Valid 012000Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SOUTHERN KANSAS TO NORTHWEST OKLAHOMA... ...SUMMARY... Isolated severe thunderstorms may occur across parts of southern Kansas and western/northern Oklahoma this afternoon and evening, with isolated large hail and damaging winds the main threats. ...20z Update... The previous forecast remains on track with only minor adjustments made to reflect recent convective trends. Initial thunderstorm development along a weak surface front is noted from northeast to southwest KS as of 19 UTC. Based on regional VWPs, mid-level flow remains relatively strongest across southern to southwest KS on the west/southwest side of the upper wave, which should promote a slightly higher potential for severe gusts and/or hail this afternoon/evening. The Marginal risk area was slightly adjusted to better capture this potential. See MCD #2025 for additional short-term details. Elsewhere, only minor adjustments to the thunder line were needed. An occasional lightning flash or two will be possible during the 09-12 UTC period across central CA, but recent guidance continues to suggest that lightning coverage/probability will likely remain below 10%. ..Moore.. 09/01/2025 .PREV DISCUSSION... /ISSUED 1122 AM CDT Mon Sep 01 2025/ ...Southern/Central Plains... A mid-level shortwave trough centered over eastern NE late this morning will move southeastward toward the southern Plains and Ozarks by tonight. This will occur in association with a belt of modestly enhanced north-northwesterly mid-level winds (around 30-40 kt at 500 mb). While the related surface response will remain muted, a weak surface front/wind shift will progress southward from KS into OK, with a relatively moist air mass preceding the advancing boundary. Ongoing low clouds/stratus should continue to gradually erode this afternoon, yielding ample insolation and a corridor of moderate instability and steepening low-level lapse rates, particularly across southern KS into northwest OK. Widely scattered thunderstorm development is probable by mid/late afternoon near the front/wind shift as the boundary layer warms. The enhanced north-northwesterly flow aloft will contribute to 30-40 kt of effective bulk shear, which should support multicell clusters and perhaps marginal supercells. Isolated severe hail/damaging winds will be possible through early evening as storms develop southward from parts of southern KS into western/northern OK. Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0225 PM CDT Mon Sep 01 2025 Valid 031200Z - 041200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS WEDNESDAY AFTERNOON AND EVENING ACROSS PARTS OF SOUTH CENTRAL AND EASTERN KANSAS INTO WESTERN AND CENTRAL MISSOURI AND PORTIONS OF NORTHEASTERN OKLAHOMA... ...SUMMARY... Strong thunderstorms may impact parts of the central Great Plains into Missouri Ozarks late Wednesday afternoon into early evening, accompanied by at least some risk for severe hail and wind. ...Discussion... Tuesday into Wednesday, models indicate little change to the amplified large-scale pattern across the mid-latitude eastern Pacific through North America. Mid/upper troughing will be maintained to the east of the Canadian/U.S. Rockies, reinforced by one vigorous short wave trough forecast to continue digging southeast of the northern Great Plains/Upper Midwest vicinity, as a similar upstream perturbation digs southeast of the Northwest Territories through eastern Canadian Prairies. A surface cold front associated with the lead impulse is forecast to continue surging southeastward through the remainder of the Midwest/lower Ohio and middle Mississippi Valleys and central Great Plains, accompanied by notable further low-level drying. Seasonably high moisture content will generally remain confined to a plume across the central Gulf Basin and Florida Peninsula into southwestern Atlantic, on the southern through southeastern periphery of the larger-scale mid/upper troughing. ...Central Great Plains into Missouri Ozarks... Mid/upper forcing for ascent overspreading the region, to the southwest of the primary digging mid-level troughing/evolving low, remains unclear due to lingering model spread. However, models suggest that boundary-layer moisture will remain sufficient to support moderate potential instability beneath a pre-frontal plume of steepening lower/mid-tropospheric lapse rates. Focusing on the southward advancing cold front, and pre-frontal surface troughing, at least isolated to widely scattered thunderstorm development appears possible by late Wednesday afternoon. Beneath strengthening northwesterly mid-level flow, the environment may become conducive to supercells and one or two small organizing clusters with potential to produce severe hail and wind, before convection weakens during the evening with the loss of daytime heating. ..Kerr.. 09/01/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0225 PM CDT Mon Sep 01 2025 Valid 031200Z - 041200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS WEDNESDAY AFTERNOON AND EVENING ACROSS PARTS OF SOUTH CENTRAL AND EASTERN KANSAS INTO WESTERN AND CENTRAL MISSOURI AND PORTIONS OF NORTHEASTERN OKLAHOMA... ...SUMMARY... Strong thunderstorms may impact parts of the central Great Plains into Missouri Ozarks late Wednesday afternoon into early evening, accompanied by at least some risk for severe hail and wind. ...Discussion... Tuesday into Wednesday, models indicate little change to the amplified large-scale pattern across the mid-latitude eastern Pacific through North America. Mid/upper troughing will be maintained to the east of the Canadian/U.S. Rockies, reinforced by one vigorous short wave trough forecast to continue digging southeast of the northern Great Plains/Upper Midwest vicinity, as a similar upstream perturbation digs southeast of the Northwest Territories through eastern Canadian Prairies. A surface cold front associated with the lead impulse is forecast to continue surging southeastward through the remainder of the Midwest/lower Ohio and middle Mississippi Valleys and central Great Plains, accompanied by notable further low-level drying. Seasonably high moisture content will generally remain confined to a plume across the central Gulf Basin and Florida Peninsula into southwestern Atlantic, on the southern through southeastern periphery of the larger-scale mid/upper troughing. ...Central Great Plains into Missouri Ozarks... Mid/upper forcing for ascent overspreading the region, to the southwest of the primary digging mid-level troughing/evolving low, remains unclear due to lingering model spread. However, models suggest that boundary-layer moisture will remain sufficient to support moderate potential instability beneath a pre-frontal plume of steepening lower/mid-tropospheric lapse rates. Focusing on the southward advancing cold front, and pre-frontal surface troughing, at least isolated to widely scattered thunderstorm development appears possible by late Wednesday afternoon. Beneath strengthening northwesterly mid-level flow, the environment may become conducive to supercells and one or two small organizing clusters with potential to produce severe hail and wind, before convection weakens during the evening with the loss of daytime heating. ..Kerr.. 09/01/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0225 PM CDT Mon Sep 01 2025 Valid 031200Z - 041200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS WEDNESDAY AFTERNOON AND EVENING ACROSS PARTS OF SOUTH CENTRAL AND EASTERN KANSAS INTO WESTERN AND CENTRAL MISSOURI AND PORTIONS OF NORTHEASTERN OKLAHOMA... ...SUMMARY... Strong thunderstorms may impact parts of the central Great Plains into Missouri Ozarks late Wednesday afternoon into early evening, accompanied by at least some risk for severe hail and wind. ...Discussion... Tuesday into Wednesday, models indicate little change to the amplified large-scale pattern across the mid-latitude eastern Pacific through North America. Mid/upper troughing will be maintained to the east of the Canadian/U.S. Rockies, reinforced by one vigorous short wave trough forecast to continue digging southeast of the northern Great Plains/Upper Midwest vicinity, as a similar upstream perturbation digs southeast of the Northwest Territories through eastern Canadian Prairies. A surface cold front associated with the lead impulse is forecast to continue surging southeastward through the remainder of the Midwest/lower Ohio and middle Mississippi Valleys and central Great Plains, accompanied by notable further low-level drying. Seasonably high moisture content will generally remain confined to a plume across the central Gulf Basin and Florida Peninsula into southwestern Atlantic, on the southern through southeastern periphery of the larger-scale mid/upper troughing. ...Central Great Plains into Missouri Ozarks... Mid/upper forcing for ascent overspreading the region, to the southwest of the primary digging mid-level troughing/evolving low, remains unclear due to lingering model spread. However, models suggest that boundary-layer moisture will remain sufficient to support moderate potential instability beneath a pre-frontal plume of steepening lower/mid-tropospheric lapse rates. Focusing on the southward advancing cold front, and pre-frontal surface troughing, at least isolated to widely scattered thunderstorm development appears possible by late Wednesday afternoon. Beneath strengthening northwesterly mid-level flow, the environment may become conducive to supercells and one or two small organizing clusters with potential to produce severe hail and wind, before convection weakens during the evening with the loss of daytime heating. ..Kerr.. 09/01/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0225 PM CDT Mon Sep 01 2025 Valid 031200Z - 041200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS WEDNESDAY AFTERNOON AND EVENING ACROSS PARTS OF SOUTH CENTRAL AND EASTERN KANSAS INTO WESTERN AND CENTRAL MISSOURI AND PORTIONS OF NORTHEASTERN OKLAHOMA... ...SUMMARY... Strong thunderstorms may impact parts of the central Great Plains into Missouri Ozarks late Wednesday afternoon into early evening, accompanied by at least some risk for severe hail and wind. ...Discussion... Tuesday into Wednesday, models indicate little change to the amplified large-scale pattern across the mid-latitude eastern Pacific through North America. Mid/upper troughing will be maintained to the east of the Canadian/U.S. Rockies, reinforced by one vigorous short wave trough forecast to continue digging southeast of the northern Great Plains/Upper Midwest vicinity, as a similar upstream perturbation digs southeast of the Northwest Territories through eastern Canadian Prairies. A surface cold front associated with the lead impulse is forecast to continue surging southeastward through the remainder of the Midwest/lower Ohio and middle Mississippi Valleys and central Great Plains, accompanied by notable further low-level drying. Seasonably high moisture content will generally remain confined to a plume across the central Gulf Basin and Florida Peninsula into southwestern Atlantic, on the southern through southeastern periphery of the larger-scale mid/upper troughing. ...Central Great Plains into Missouri Ozarks... Mid/upper forcing for ascent overspreading the region, to the southwest of the primary digging mid-level troughing/evolving low, remains unclear due to lingering model spread. However, models suggest that boundary-layer moisture will remain sufficient to support moderate potential instability beneath a pre-frontal plume of steepening lower/mid-tropospheric lapse rates. Focusing on the southward advancing cold front, and pre-frontal surface troughing, at least isolated to widely scattered thunderstorm development appears possible by late Wednesday afternoon. Beneath strengthening northwesterly mid-level flow, the environment may become conducive to supercells and one or two small organizing clusters with potential to produce severe hail and wind, before convection weakens during the evening with the loss of daytime heating. ..Kerr.. 09/01/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0225 PM CDT Mon Sep 01 2025 Valid 031200Z - 041200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS WEDNESDAY AFTERNOON AND EVENING ACROSS PARTS OF SOUTH CENTRAL AND EASTERN KANSAS INTO WESTERN AND CENTRAL MISSOURI AND PORTIONS OF NORTHEASTERN OKLAHOMA... ...SUMMARY... Strong thunderstorms may impact parts of the central Great Plains into Missouri Ozarks late Wednesday afternoon into early evening, accompanied by at least some risk for severe hail and wind. ...Discussion... Tuesday into Wednesday, models indicate little change to the amplified large-scale pattern across the mid-latitude eastern Pacific through North America. Mid/upper troughing will be maintained to the east of the Canadian/U.S. Rockies, reinforced by one vigorous short wave trough forecast to continue digging southeast of the northern Great Plains/Upper Midwest vicinity, as a similar upstream perturbation digs southeast of the Northwest Territories through eastern Canadian Prairies. A surface cold front associated with the lead impulse is forecast to continue surging southeastward through the remainder of the Midwest/lower Ohio and middle Mississippi Valleys and central Great Plains, accompanied by notable further low-level drying. Seasonably high moisture content will generally remain confined to a plume across the central Gulf Basin and Florida Peninsula into southwestern Atlantic, on the southern through southeastern periphery of the larger-scale mid/upper troughing. ...Central Great Plains into Missouri Ozarks... Mid/upper forcing for ascent overspreading the region, to the southwest of the primary digging mid-level troughing/evolving low, remains unclear due to lingering model spread. However, models suggest that boundary-layer moisture will remain sufficient to support moderate potential instability beneath a pre-frontal plume of steepening lower/mid-tropospheric lapse rates. Focusing on the southward advancing cold front, and pre-frontal surface troughing, at least isolated to widely scattered thunderstorm development appears possible by late Wednesday afternoon. Beneath strengthening northwesterly mid-level flow, the environment may become conducive to supercells and one or two small organizing clusters with potential to produce severe hail and wind, before convection weakens during the evening with the loss of daytime heating. ..Kerr.. 09/01/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0225 PM CDT Mon Sep 01 2025 Valid 031200Z - 041200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS WEDNESDAY AFTERNOON AND EVENING ACROSS PARTS OF SOUTH CENTRAL AND EASTERN KANSAS INTO WESTERN AND CENTRAL MISSOURI AND PORTIONS OF NORTHEASTERN OKLAHOMA... ...SUMMARY... Strong thunderstorms may impact parts of the central Great Plains into Missouri Ozarks late Wednesday afternoon into early evening, accompanied by at least some risk for severe hail and wind. ...Discussion... Tuesday into Wednesday, models indicate little change to the amplified large-scale pattern across the mid-latitude eastern Pacific through North America. Mid/upper troughing will be maintained to the east of the Canadian/U.S. Rockies, reinforced by one vigorous short wave trough forecast to continue digging southeast of the northern Great Plains/Upper Midwest vicinity, as a similar upstream perturbation digs southeast of the Northwest Territories through eastern Canadian Prairies. A surface cold front associated with the lead impulse is forecast to continue surging southeastward through the remainder of the Midwest/lower Ohio and middle Mississippi Valleys and central Great Plains, accompanied by notable further low-level drying. Seasonably high moisture content will generally remain confined to a plume across the central Gulf Basin and Florida Peninsula into southwestern Atlantic, on the southern through southeastern periphery of the larger-scale mid/upper troughing. ...Central Great Plains into Missouri Ozarks... Mid/upper forcing for ascent overspreading the region, to the southwest of the primary digging mid-level troughing/evolving low, remains unclear due to lingering model spread. However, models suggest that boundary-layer moisture will remain sufficient to support moderate potential instability beneath a pre-frontal plume of steepening lower/mid-tropospheric lapse rates. Focusing on the southward advancing cold front, and pre-frontal surface troughing, at least isolated to widely scattered thunderstorm development appears possible by late Wednesday afternoon. Beneath strengthening northwesterly mid-level flow, the environment may become conducive to supercells and one or two small organizing clusters with potential to produce severe hail and wind, before convection weakens during the evening with the loss of daytime heating. ..Kerr.. 09/01/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0225 PM CDT Mon Sep 01 2025 Valid 031200Z - 041200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS WEDNESDAY AFTERNOON AND EVENING ACROSS PARTS OF SOUTH CENTRAL AND EASTERN KANSAS INTO WESTERN AND CENTRAL MISSOURI AND PORTIONS OF NORTHEASTERN OKLAHOMA... ...SUMMARY... Strong thunderstorms may impact parts of the central Great Plains into Missouri Ozarks late Wednesday afternoon into early evening, accompanied by at least some risk for severe hail and wind. ...Discussion... Tuesday into Wednesday, models indicate little change to the amplified large-scale pattern across the mid-latitude eastern Pacific through North America. Mid/upper troughing will be maintained to the east of the Canadian/U.S. Rockies, reinforced by one vigorous short wave trough forecast to continue digging southeast of the northern Great Plains/Upper Midwest vicinity, as a similar upstream perturbation digs southeast of the Northwest Territories through eastern Canadian Prairies. A surface cold front associated with the lead impulse is forecast to continue surging southeastward through the remainder of the Midwest/lower Ohio and middle Mississippi Valleys and central Great Plains, accompanied by notable further low-level drying. Seasonably high moisture content will generally remain confined to a plume across the central Gulf Basin and Florida Peninsula into southwestern Atlantic, on the southern through southeastern periphery of the larger-scale mid/upper troughing. ...Central Great Plains into Missouri Ozarks... Mid/upper forcing for ascent overspreading the region, to the southwest of the primary digging mid-level troughing/evolving low, remains unclear due to lingering model spread. However, models suggest that boundary-layer moisture will remain sufficient to support moderate potential instability beneath a pre-frontal plume of steepening lower/mid-tropospheric lapse rates. Focusing on the southward advancing cold front, and pre-frontal surface troughing, at least isolated to widely scattered thunderstorm development appears possible by late Wednesday afternoon. Beneath strengthening northwesterly mid-level flow, the environment may become conducive to supercells and one or two small organizing clusters with potential to produce severe hail and wind, before convection weakens during the evening with the loss of daytime heating. ..Kerr.. 09/01/2025 Read more