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SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1124 AM CDT Sun Aug 25 2019 Valid 251630Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON INTO TONIGHT FROM THE DAKOTAS INTO NORTHERN NE... ...SUMMARY... Thunderstorms with large hail and a few damaging gusts are expected over parts of the Dakotas this afternoon/evening into northern Nebraska overnight. ...Dakotas to NE this afternoon into tonight... A northern stream shortwave trough will amplify over the northern High Plains through tonight. An initial surface trough/cold front across the western Dakotas will continue eastward into the eastern Dakotas and southeastward into NE by the end of the period. A narrow zone of surface heating along the surface trough and weak large-scale ascent will support thunderstorm development this afternoon/evening across the central Dakotas, and storms will subsequently spread eastward and southeastward tonight. Steep midlevel lapse rates will combine with the surface heating and boundary-layer dewpoints in the mid 60s to result in MLCAPE of 1500-2500 J/kg immediately east of the surface trough this afternoon. Deep-layer vertical shear with straight hodographs will initially favor supercells capable of producing large hail, though upscale growth into clusters/line segments with damaging winds appears probable this evening before the convection begins to spread east of the stronger buoyancy. The southern flank of the frontal convection is likely to maintain intensity the longest, potentially developing southward into NE in conjunction with the surface triple point and warm advection on the nose of 30-40 kt nocturnal low-level jet. Other more isolated storms will be possible later this evening from the Big Horns into southwestern SD, in the immediate post-frontal upslope flow regime. Deep-layer vertical shear will be favorable for supercells, though limited moisture/buoyancy should tend to temper the hail/wind threat somewhat. ...OK/AR/MO this afternoon... A convectively enhanced midlevel trough is moving eastward over eastern KS and northeastern OK as of mid morning. Vertical shear will be strongest to the west of the trough in conjunction with the stronger northwesterly midlevel flow. However, storm initiation beyond ongoing convection in the warm advection zone near I-35 along the KS/OK border is unlikely given the expected onset of subsidence in the wake of the midlevel trough. Some destabilization is expected south through east of the convective outflow, though clouds are relatively widespread and will likely continue to slow surface heating. Overall, it appears that a marginal threat for damaging wind is the primary concern with multicell clusters along the outflow boundary this afternoon from southern MO into northwestern AR and southeastern OK. ..Thompson/Cook.. 08/25/2019 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1124 AM CDT Sun Aug 25 2019 Valid 251630Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON INTO TONIGHT FROM THE DAKOTAS INTO NORTHERN NE... ...SUMMARY... Thunderstorms with large hail and a few damaging gusts are expected over parts of the Dakotas this afternoon/evening into northern Nebraska overnight. ...Dakotas to NE this afternoon into tonight... A northern stream shortwave trough will amplify over the northern High Plains through tonight. An initial surface trough/cold front across the western Dakotas will continue eastward into the eastern Dakotas and southeastward into NE by the end of the period. A narrow zone of surface heating along the surface trough and weak large-scale ascent will support thunderstorm development this afternoon/evening across the central Dakotas, and storms will subsequently spread eastward and southeastward tonight. Steep midlevel lapse rates will combine with the surface heating and boundary-layer dewpoints in the mid 60s to result in MLCAPE of 1500-2500 J/kg immediately east of the surface trough this afternoon. Deep-layer vertical shear with straight hodographs will initially favor supercells capable of producing large hail, though upscale growth into clusters/line segments with damaging winds appears probable this evening before the convection begins to spread east of the stronger buoyancy. The southern flank of the frontal convection is likely to maintain intensity the longest, potentially developing southward into NE in conjunction with the surface triple point and warm advection on the nose of 30-40 kt nocturnal low-level jet. Other more isolated storms will be possible later this evening from the Big Horns into southwestern SD, in the immediate post-frontal upslope flow regime. Deep-layer vertical shear will be favorable for supercells, though limited moisture/buoyancy should tend to temper the hail/wind threat somewhat. ...OK/AR/MO this afternoon... A convectively enhanced midlevel trough is moving eastward over eastern KS and northeastern OK as of mid morning. Vertical shear will be strongest to the west of the trough in conjunction with the stronger northwesterly midlevel flow. However, storm initiation beyond ongoing convection in the warm advection zone near I-35 along the KS/OK border is unlikely given the expected onset of subsidence in the wake of the midlevel trough. Some destabilization is expected south through east of the convective outflow, though clouds are relatively widespread and will likely continue to slow surface heating. Overall, it appears that a marginal threat for damaging wind is the primary concern with multicell clusters along the outflow boundary this afternoon from southern MO into northwestern AR and southeastern OK. ..Thompson/Cook.. 08/25/2019 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1124 AM CDT Sun Aug 25 2019 Valid 251630Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON INTO TONIGHT FROM THE DAKOTAS INTO NORTHERN NE... ...SUMMARY... Thunderstorms with large hail and a few damaging gusts are expected over parts of the Dakotas this afternoon/evening into northern Nebraska overnight. ...Dakotas to NE this afternoon into tonight... A northern stream shortwave trough will amplify over the northern High Plains through tonight. An initial surface trough/cold front across the western Dakotas will continue eastward into the eastern Dakotas and southeastward into NE by the end of the period. A narrow zone of surface heating along the surface trough and weak large-scale ascent will support thunderstorm development this afternoon/evening across the central Dakotas, and storms will subsequently spread eastward and southeastward tonight. Steep midlevel lapse rates will combine with the surface heating and boundary-layer dewpoints in the mid 60s to result in MLCAPE of 1500-2500 J/kg immediately east of the surface trough this afternoon. Deep-layer vertical shear with straight hodographs will initially favor supercells capable of producing large hail, though upscale growth into clusters/line segments with damaging winds appears probable this evening before the convection begins to spread east of the stronger buoyancy. The southern flank of the frontal convection is likely to maintain intensity the longest, potentially developing southward into NE in conjunction with the surface triple point and warm advection on the nose of 30-40 kt nocturnal low-level jet. Other more isolated storms will be possible later this evening from the Big Horns into southwestern SD, in the immediate post-frontal upslope flow regime. Deep-layer vertical shear will be favorable for supercells, though limited moisture/buoyancy should tend to temper the hail/wind threat somewhat. ...OK/AR/MO this afternoon... A convectively enhanced midlevel trough is moving eastward over eastern KS and northeastern OK as of mid morning. Vertical shear will be strongest to the west of the trough in conjunction with the stronger northwesterly midlevel flow. However, storm initiation beyond ongoing convection in the warm advection zone near I-35 along the KS/OK border is unlikely given the expected onset of subsidence in the wake of the midlevel trough. Some destabilization is expected south through east of the convective outflow, though clouds are relatively widespread and will likely continue to slow surface heating. Overall, it appears that a marginal threat for damaging wind is the primary concern with multicell clusters along the outflow boundary this afternoon from southern MO into northwestern AR and southeastern OK. ..Thompson/Cook.. 08/25/2019 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1124 AM CDT Sun Aug 25 2019 Valid 251630Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON INTO TONIGHT FROM THE DAKOTAS INTO NORTHERN NE... ...SUMMARY... Thunderstorms with large hail and a few damaging gusts are expected over parts of the Dakotas this afternoon/evening into northern Nebraska overnight. ...Dakotas to NE this afternoon into tonight... A northern stream shortwave trough will amplify over the northern High Plains through tonight. An initial surface trough/cold front across the western Dakotas will continue eastward into the eastern Dakotas and southeastward into NE by the end of the period. A narrow zone of surface heating along the surface trough and weak large-scale ascent will support thunderstorm development this afternoon/evening across the central Dakotas, and storms will subsequently spread eastward and southeastward tonight. Steep midlevel lapse rates will combine with the surface heating and boundary-layer dewpoints in the mid 60s to result in MLCAPE of 1500-2500 J/kg immediately east of the surface trough this afternoon. Deep-layer vertical shear with straight hodographs will initially favor supercells capable of producing large hail, though upscale growth into clusters/line segments with damaging winds appears probable this evening before the convection begins to spread east of the stronger buoyancy. The southern flank of the frontal convection is likely to maintain intensity the longest, potentially developing southward into NE in conjunction with the surface triple point and warm advection on the nose of 30-40 kt nocturnal low-level jet. Other more isolated storms will be possible later this evening from the Big Horns into southwestern SD, in the immediate post-frontal upslope flow regime. Deep-layer vertical shear will be favorable for supercells, though limited moisture/buoyancy should tend to temper the hail/wind threat somewhat. ...OK/AR/MO this afternoon... A convectively enhanced midlevel trough is moving eastward over eastern KS and northeastern OK as of mid morning. Vertical shear will be strongest to the west of the trough in conjunction with the stronger northwesterly midlevel flow. However, storm initiation beyond ongoing convection in the warm advection zone near I-35 along the KS/OK border is unlikely given the expected onset of subsidence in the wake of the midlevel trough. Some destabilization is expected south through east of the convective outflow, though clouds are relatively widespread and will likely continue to slow surface heating. Overall, it appears that a marginal threat for damaging wind is the primary concern with multicell clusters along the outflow boundary this afternoon from southern MO into northwestern AR and southeastern OK. ..Thompson/Cook.. 08/25/2019 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1031 AM CDT Sun Aug 25 2019 Valid 251700Z - 261200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF NORTHEAST NEVADA...SOUTHERN IDAHO...NORTHERN UTAH...SOUTHERN WYOMING...NORTHWEST COLORADO... The critical areas were joined and minor modifications were made elsewhere based on latest guidance and observations. The forecast remains on track, and please see the discussion below for more details. ..Nauslar.. 08/25/2019 .PREV DISCUSSION... /ISSUED 0109 AM CDT Sun Aug 25 2019/ ...Synopsis... A strong mid-level jet will push into the central Rockies today, on the back side of a broad upper-level trough along the Canadian border. At the surface, a cold front will move across the Intermountain West. Boundary-layer mixing of stronger flow aloft along with a more stout surface pressure gradient than recent days will lead to critical fire weather conditions across portions of both the northern Great Basin and central Rockies. Winds of 20-25 mph will be common across the highlighted critical area. Potential for 25+ mph sustained winds, and higher gusts, will be maximized underneath the mid-level jet core in the Snake River Valley and southern Wyoming. Elevated conditions will occur surrounding the critical area as winds in these locations will either be lighter (15-20 mph) and/or fuels will be slightly less receptive to fire spread. All areas that have been highlighted can expect 10-15% RH during the afternoon. Only minor changes have been made from the previous forecast on account of the latest guidance. The critical area in northeast Nevada was expanded slightly westward and the elevated area was expanded to include more of central Colorado. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1031 AM CDT Sun Aug 25 2019 Valid 251700Z - 261200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF NORTHEAST NEVADA...SOUTHERN IDAHO...NORTHERN UTAH...SOUTHERN WYOMING...NORTHWEST COLORADO... The critical areas were joined and minor modifications were made elsewhere based on latest guidance and observations. The forecast remains on track, and please see the discussion below for more details. ..Nauslar.. 08/25/2019 .PREV DISCUSSION... /ISSUED 0109 AM CDT Sun Aug 25 2019/ ...Synopsis... A strong mid-level jet will push into the central Rockies today, on the back side of a broad upper-level trough along the Canadian border. At the surface, a cold front will move across the Intermountain West. Boundary-layer mixing of stronger flow aloft along with a more stout surface pressure gradient than recent days will lead to critical fire weather conditions across portions of both the northern Great Basin and central Rockies. Winds of 20-25 mph will be common across the highlighted critical area. Potential for 25+ mph sustained winds, and higher gusts, will be maximized underneath the mid-level jet core in the Snake River Valley and southern Wyoming. Elevated conditions will occur surrounding the critical area as winds in these locations will either be lighter (15-20 mph) and/or fuels will be slightly less receptive to fire spread. All areas that have been highlighted can expect 10-15% RH during the afternoon. Only minor changes have been made from the previous forecast on account of the latest guidance. The critical area in northeast Nevada was expanded slightly westward and the elevated area was expanded to include more of central Colorado. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1031 AM CDT Sun Aug 25 2019 Valid 251700Z - 261200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF NORTHEAST NEVADA...SOUTHERN IDAHO...NORTHERN UTAH...SOUTHERN WYOMING...NORTHWEST COLORADO... The critical areas were joined and minor modifications were made elsewhere based on latest guidance and observations. The forecast remains on track, and please see the discussion below for more details. ..Nauslar.. 08/25/2019 .PREV DISCUSSION... /ISSUED 0109 AM CDT Sun Aug 25 2019/ ...Synopsis... A strong mid-level jet will push into the central Rockies today, on the back side of a broad upper-level trough along the Canadian border. At the surface, a cold front will move across the Intermountain West. Boundary-layer mixing of stronger flow aloft along with a more stout surface pressure gradient than recent days will lead to critical fire weather conditions across portions of both the northern Great Basin and central Rockies. Winds of 20-25 mph will be common across the highlighted critical area. Potential for 25+ mph sustained winds, and higher gusts, will be maximized underneath the mid-level jet core in the Snake River Valley and southern Wyoming. Elevated conditions will occur surrounding the critical area as winds in these locations will either be lighter (15-20 mph) and/or fuels will be slightly less receptive to fire spread. All areas that have been highlighted can expect 10-15% RH during the afternoon. Only minor changes have been made from the previous forecast on account of the latest guidance. The critical area in northeast Nevada was expanded slightly westward and the elevated area was expanded to include more of central Colorado. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1031 AM CDT Sun Aug 25 2019 Valid 251700Z - 261200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF NORTHEAST NEVADA...SOUTHERN IDAHO...NORTHERN UTAH...SOUTHERN WYOMING...NORTHWEST COLORADO... The critical areas were joined and minor modifications were made elsewhere based on latest guidance and observations. The forecast remains on track, and please see the discussion below for more details. ..Nauslar.. 08/25/2019 .PREV DISCUSSION... /ISSUED 0109 AM CDT Sun Aug 25 2019/ ...Synopsis... A strong mid-level jet will push into the central Rockies today, on the back side of a broad upper-level trough along the Canadian border. At the surface, a cold front will move across the Intermountain West. Boundary-layer mixing of stronger flow aloft along with a more stout surface pressure gradient than recent days will lead to critical fire weather conditions across portions of both the northern Great Basin and central Rockies. Winds of 20-25 mph will be common across the highlighted critical area. Potential for 25+ mph sustained winds, and higher gusts, will be maximized underneath the mid-level jet core in the Snake River Valley and southern Wyoming. Elevated conditions will occur surrounding the critical area as winds in these locations will either be lighter (15-20 mph) and/or fuels will be slightly less receptive to fire spread. All areas that have been highlighted can expect 10-15% RH during the afternoon. Only minor changes have been made from the previous forecast on account of the latest guidance. The critical area in northeast Nevada was expanded slightly westward and the elevated area was expanded to include more of central Colorado. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

5-Day Uncertainty Track last updated Sun, 25 Aug 2019 14:35:17 GMT


Wind Speed Probabilities last updated Sun, 25 Aug 2019 15:31:16 GMT

Issued at 800 AM PDT Sun Aug 25 2019 000 WTPZ45 KNHC 251433 TCDEP5 Tropical Depression Ivo Discussion Number 18 NWS National Hurricane Center Miami FL EP102019 800 AM PDT Sun Aug 25 2019 Ivo is moving north-northwestward or 340/10 kt, and that motion is forecast to continue today. A turn to the north with a gradual decrease in forward speed is still expected to occur on Monday, and that motion should continue into Tuesday. The new NHC track forecast is similar to the previous advisory track and lies close a blend of the consensus models HCCA, TVCN, and TVCX. The initial intensity of 25 kt is based on earlier ASCAT surface wind data. Although a small area of deep convection has redeveloped about 100 n mi north of the low-level center, that thunderstorm activity is too far away to provide any positive feedback onto the circulation. Thus, Ivo basically remains devoid of any significant organized convection, and this downward trend is expected to continue for the next 48 hours while the cyclone moves of waters cooler than 22C. As a result of the expected spin down of the shallow vortex, Ivo is forecast to become a post-tropical remnant low later today and dissipate by Tuesday. Although Ivo is weakening, significant swells generated by the cyclone are affecting portions of the west coast of the Baja California peninsula and southern California. These swells are likely to continue through the day and could cause rip currents, and gradually subside on Monday. See products from your local weather office for additional information. FORECAST POSITIONS AND MAX WINDS INIT 25/1500Z 25.5N 117.4W 25 KT 30 MPH 12H 26/0000Z 26.7N 118.0W 20 KT 25 MPH...POST-TROP/REMNT LOW 24H 26/1200Z 27.5N 118.1W 20 KT 25 MPH...POST-TROP/REMNT LOW 36H 27/0000Z 28.3N 118.1W 15 KT 15 MPH...POST-TROP/REMNT LOW 48H 27/1200Z...DISSIPATED $$ Forecaster Stewart

Issued at 1500 UTC SUN AUG 25 2019 000 FOPZ15 KNHC 251432 PWSEP5 TROPICAL DEPRESSION IVO WIND SPEED PROBABILITIES NUMBER 18 NWS NATIONAL HURRICANE CENTER MIAMI FL EP102019 1500 UTC SUN AUG 25 2019 AT 1500Z THE CENTER OF TROPICAL DEPRESSION IVO WAS LOCATED NEAR LATITUDE 25.5 NORTH...LONGITUDE 117.4 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 25 KTS...30 MPH...45 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 12Z SUN 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 12Z SUN 00Z MON 12Z MON 00Z TUE 12Z TUE 12Z WED 12Z THU PERIODS TO TO TO TO TO TO TO 00Z MON 12Z MON 00Z TUE 12Z TUE 12Z WED 12Z THU 12Z FRI FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT IS GUADALUPE 34 X 1( 1) 2( 3) X( 3) X( 3) X( 3) X( 3) $$ FORECASTER STEWART

Issued at 1500 UTC SUN AUG 25 2019 000 WTPZ25 KNHC 251432 TCMEP5 TROPICAL DEPRESSION IVO FORECAST/ADVISORY NUMBER 18 NWS NATIONAL HURRICANE CENTER MIAMI FL EP102019 1500 UTC SUN AUG 25 2019 THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT. TROPICAL DEPRESSION CENTER LOCATED NEAR 25.5N 117.4W AT 25/1500Z POSITION ACCURATE WITHIN 25 NM PRESENT MOVEMENT TOWARD THE NORTH-NORTHWEST OR 340 DEGREES AT 10 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1007 MB MAX SUSTAINED WINDS 25 KT WITH GUSTS TO 35 KT. 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 25.5N 117.4W AT 25/1500Z AT 25/1200Z CENTER WAS LOCATED NEAR 25.0N 117.2W FORECAST VALID 26/0000Z 26.7N 118.0W...POST-TROP/REMNT LOW MAX WIND 20 KT...GUSTS 30 KT. FORECAST VALID 26/1200Z 27.5N 118.1W...POST-TROP/REMNT LOW MAX WIND 20 KT...GUSTS 30 KT. FORECAST VALID 27/0000Z 28.3N 118.1W...POST-TROP/REMNT LOW MAX WIND 15 KT...GUSTS 20 KT. FORECAST VALID 27/1200Z...DISSIPATED REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 25.5N 117.4W NEXT ADVISORY AT 25/2100Z $$ FORECASTER STEWART

Issued at 800 AM PDT Sun Aug 25 2019 000 WTPZ35 KNHC 251432 TCPEP5 BULLETIN Tropical Depression Ivo Advisory Number 18 NWS National Hurricane Center Miami FL EP102019 800 AM PDT Sun Aug 25 2019 ...IVO EXPECTED TO BECOME A REMNANT LOW LATER TODAY... SUMMARY OF 800 AM PDT...1500 UTC...INFORMATION ---------------------------------------------- LOCATION...25.5N 117.4W ABOUT 505 MI...815 KM WNW OF THE SOUTHERN TIP OF BAJA CALIFORNIA MAXIMUM SUSTAINED WINDS...30 MPH...45 KM/H PRESENT MOVEMENT...NNW OR 340 DEGREES AT 12 MPH...19 KM/H MINIMUM CENTRAL PRESSURE...1007 MB...29.74 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 800 AM PDT (1500 UTC), the center of Tropical Depression Ivo was located near latitude 25.5 North, longitude 117.4 West. The depression is moving toward the north-northwest near 12 mph (19 km/h), and this motion is expected to continue today. A decrease in forward speed and a turn to the north is forecast to occur tonight and Monday. Maximum sustained winds have decreased to near 30 mph (45 km/h) with higher gusts. Additional weakening is forecast during the next 48 hours, and Ivo is forecast to degenerate to a remnant low later today and dissipate by Tuesday. The estimated minimum central pressure is 1007 mb (29.74 inches). HAZARDS AFFECTING LAND ---------------------- SURF: Swells generated by Ivo are affecting the west coast of the Baja California peninsula and portions of the southern California coastline. These swells are likely to continue through today and could cause life-threatening surf and rip currents. Please consult products from your local weather office. NEXT ADVISORY ------------- Next complete advisory at 200 PM PDT. $$ Forecaster Stewart

...IVO EXPECTED TO BECOME A REMNANT LOW LATER TODAY... As of 8:00 AM PDT Sun Aug 25 the center of Ivo was located near 25.5, -117.4 with movement NNW at 12 mph. The minimum central pressure was 1007 mb with maximum sustained winds of about 30 mph.

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0753 AM CDT Sun Aug 25 2019 Valid 251300Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE DAKOTAS AND NORTHWESTERN MINNESOTA THIS AFTERNOON AND EVENING... ...SUMMARY... Thunderstorms with severe hail and severe gusts are expected over parts of the Dakotas and northwestern Minnesota this afternoon and evening. ...Synopsis... The mid/upper-level pattern will continue to be dominated by a mean negatively tilted trough from western Canada across the central CONUS to the lower Mississippi Valley region. The associated belt of greatest northern-stream cyclonic flow will shift eastward from the Pacific Northwest across the northern Rockies and northern Plains through the period, with height falls and difluent flow spreading over the Dakotas. Several low-amplitude shortwaves are embedded in that cyclonic-flow field. The leading one -- now apparent in moisture-channel imagery over the central Dakotas -- will move eastward across MN today and this evening, while weakening. This feature will be followed closely by another over eastern MT and northeastern WY, and still another initially located over southern BC and WA. The latter trough will be the strongest by tonight, while crossing MT. Farther southeast near the mean trough, a series of slower-moving, mesoscale trough in midlevels, anchored by MCVs, will populate the skies. The best-defined MCV in satellite and composited radar imagery is located over northeastern KS in the MHK/FRI area. The associated perturbation should move eastward over MO through the period. Meanwhile, a pre-existing height weakness near the LA Gulf Coast will phase with the mean trough as heights fall south of the MCV-related perturbation. At the surface, 11Z analysis depicted a quasistationary frontal zone from the Mid-South region across northern AR and southwestern MO, intercepted by outflow over the southern KS/MO border, then evident again across east-central portions of NE and SD. Where not baroclinically overwhelmed by MCS outflow, this boundary should move little through the period, except for some weak eastward-moving/ warm-frontal behavior over the eastern Dakotas/Red River of the North region. A weak cold front, analyzed from a low NE of GGW southwestward across eastern MT, and a prefrontal/lee trough, will move eastward to western ND during the day. ...Dakotas/northwestern MN... Scattered thunderstorms are expected to develop this afternoon as convergence related to the weak front and a surface trough impinge om a corridor of favorable moisture and buoyancy. A mix of organized multicells and a few supercells is expected, with large hail and severe gusts possible, while a tornado cannot be ruled out. As height falls and cooling/destabilization aloft spread across the warm sector, diurnal heating will further contribute to steepening deep-layer lapse rates, atop a plume of 60s F surface dew points near and west of the eastern frontal zone. Modified RAOBs and model soundings indicate that the peak MLCAPE -- behind the morning clouds/convection related to the initial perturbation -- should reach 2000-2500 J/kg, despite patchy cloud cover. 35-45 kt effective-shear magnitudes will support convective organization, as will strong upper-level/ventilating winds. Low-level flow will be modest and, in much of the area, veered west of southerly, limiting hodograph size. Overall weakening of convection is expected late evening into the overnight hours as remaining activity moves deeper into/atop a progressively more-stable boundary layer within and east of the slow-moving surface warm-frontal zone. In each outlook level, slightly more room as been allotted for this process to occur into northwestern MN. ...Southern Plains to Ozarks region... Isolated gusts near severe limits still may occur with ongoing convection moving southeastward from the END area over central OK, before it weakens. See SPC mesoscale discussion 1856 for additional near-term details. Otherwise, widely scattered to scattered thunderstorms are expected to develop through this afternoon over portions of the Ozarks and vicinity, amidst rich low-level moisture (70s F surface dew points, roughly 2-inch PW) and minimal MLCINH. Activity should be focused along and ahead of the outflow boundaries from the morning MCS activity over portions of KS/OK. A general westward increase in midlevel lapse rates, combined with surface diabatic heating and aforementioned moisture, should contribute to MLCAPE ranging from around 3500 J/kg over parts of eastern OK to 1000-1500 J/kg in the frontal zone across the Ozarks region. Although some large-scale support may be provided in the form of weak DCVA and/or mesobeta- scale midlevel gradient-flow enhancement around the MCV(s), overall organization of the convection should be loose and multicellular in nature given weak low-level shear and modest mid/upper winds in most of the region. Damaging to severe gusts are possible in strongly water-loaded downdrafts, but the unconditional severe threat appears isolated and marginal. ..Edwards/Gleason.. 08/25/2019 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0753 AM CDT Sun Aug 25 2019 Valid 251300Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE DAKOTAS AND NORTHWESTERN MINNESOTA THIS AFTERNOON AND EVENING... ...SUMMARY... Thunderstorms with severe hail and severe gusts are expected over parts of the Dakotas and northwestern Minnesota this afternoon and evening. ...Synopsis... The mid/upper-level pattern will continue to be dominated by a mean negatively tilted trough from western Canada across the central CONUS to the lower Mississippi Valley region. The associated belt of greatest northern-stream cyclonic flow will shift eastward from the Pacific Northwest across the northern Rockies and northern Plains through the period, with height falls and difluent flow spreading over the Dakotas. Several low-amplitude shortwaves are embedded in that cyclonic-flow field. The leading one -- now apparent in moisture-channel imagery over the central Dakotas -- will move eastward across MN today and this evening, while weakening. This feature will be followed closely by another over eastern MT and northeastern WY, and still another initially located over southern BC and WA. The latter trough will be the strongest by tonight, while crossing MT. Farther southeast near the mean trough, a series of slower-moving, mesoscale trough in midlevels, anchored by MCVs, will populate the skies. The best-defined MCV in satellite and composited radar imagery is located over northeastern KS in the MHK/FRI area. The associated perturbation should move eastward over MO through the period. Meanwhile, a pre-existing height weakness near the LA Gulf Coast will phase with the mean trough as heights fall south of the MCV-related perturbation. At the surface, 11Z analysis depicted a quasistationary frontal zone from the Mid-South region across northern AR and southwestern MO, intercepted by outflow over the southern KS/MO border, then evident again across east-central portions of NE and SD. Where not baroclinically overwhelmed by MCS outflow, this boundary should move little through the period, except for some weak eastward-moving/ warm-frontal behavior over the eastern Dakotas/Red River of the North region. A weak cold front, analyzed from a low NE of GGW southwestward across eastern MT, and a prefrontal/lee trough, will move eastward to western ND during the day. ...Dakotas/northwestern MN... Scattered thunderstorms are expected to develop this afternoon as convergence related to the weak front and a surface trough impinge om a corridor of favorable moisture and buoyancy. A mix of organized multicells and a few supercells is expected, with large hail and severe gusts possible, while a tornado cannot be ruled out. As height falls and cooling/destabilization aloft spread across the warm sector, diurnal heating will further contribute to steepening deep-layer lapse rates, atop a plume of 60s F surface dew points near and west of the eastern frontal zone. Modified RAOBs and model soundings indicate that the peak MLCAPE -- behind the morning clouds/convection related to the initial perturbation -- should reach 2000-2500 J/kg, despite patchy cloud cover. 35-45 kt effective-shear magnitudes will support convective organization, as will strong upper-level/ventilating winds. Low-level flow will be modest and, in much of the area, veered west of southerly, limiting hodograph size. Overall weakening of convection is expected late evening into the overnight hours as remaining activity moves deeper into/atop a progressively more-stable boundary layer within and east of the slow-moving surface warm-frontal zone. In each outlook level, slightly more room as been allotted for this process to occur into northwestern MN. ...Southern Plains to Ozarks region... Isolated gusts near severe limits still may occur with ongoing convection moving southeastward from the END area over central OK, before it weakens. See SPC mesoscale discussion 1856 for additional near-term details. Otherwise, widely scattered to scattered thunderstorms are expected to develop through this afternoon over portions of the Ozarks and vicinity, amidst rich low-level moisture (70s F surface dew points, roughly 2-inch PW) and minimal MLCINH. Activity should be focused along and ahead of the outflow boundaries from the morning MCS activity over portions of KS/OK. A general westward increase in midlevel lapse rates, combined with surface diabatic heating and aforementioned moisture, should contribute to MLCAPE ranging from around 3500 J/kg over parts of eastern OK to 1000-1500 J/kg in the frontal zone across the Ozarks region. Although some large-scale support may be provided in the form of weak DCVA and/or mesobeta- scale midlevel gradient-flow enhancement around the MCV(s), overall organization of the convection should be loose and multicellular in nature given weak low-level shear and modest mid/upper winds in most of the region. Damaging to severe gusts are possible in strongly water-loaded downdrafts, but the unconditional severe threat appears isolated and marginal. ..Edwards/Gleason.. 08/25/2019 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0753 AM CDT Sun Aug 25 2019 Valid 251300Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE DAKOTAS AND NORTHWESTERN MINNESOTA THIS AFTERNOON AND EVENING... ...SUMMARY... Thunderstorms with severe hail and severe gusts are expected over parts of the Dakotas and northwestern Minnesota this afternoon and evening. ...Synopsis... The mid/upper-level pattern will continue to be dominated by a mean negatively tilted trough from western Canada across the central CONUS to the lower Mississippi Valley region. The associated belt of greatest northern-stream cyclonic flow will shift eastward from the Pacific Northwest across the northern Rockies and northern Plains through the period, with height falls and difluent flow spreading over the Dakotas. Several low-amplitude shortwaves are embedded in that cyclonic-flow field. The leading one -- now apparent in moisture-channel imagery over the central Dakotas -- will move eastward across MN today and this evening, while weakening. This feature will be followed closely by another over eastern MT and northeastern WY, and still another initially located over southern BC and WA. The latter trough will be the strongest by tonight, while crossing MT. Farther southeast near the mean trough, a series of slower-moving, mesoscale trough in midlevels, anchored by MCVs, will populate the skies. The best-defined MCV in satellite and composited radar imagery is located over northeastern KS in the MHK/FRI area. The associated perturbation should move eastward over MO through the period. Meanwhile, a pre-existing height weakness near the LA Gulf Coast will phase with the mean trough as heights fall south of the MCV-related perturbation. At the surface, 11Z analysis depicted a quasistationary frontal zone from the Mid-South region across northern AR and southwestern MO, intercepted by outflow over the southern KS/MO border, then evident again across east-central portions of NE and SD. Where not baroclinically overwhelmed by MCS outflow, this boundary should move little through the period, except for some weak eastward-moving/ warm-frontal behavior over the eastern Dakotas/Red River of the North region. A weak cold front, analyzed from a low NE of GGW southwestward across eastern MT, and a prefrontal/lee trough, will move eastward to western ND during the day. ...Dakotas/northwestern MN... Scattered thunderstorms are expected to develop this afternoon as convergence related to the weak front and a surface trough impinge om a corridor of favorable moisture and buoyancy. A mix of organized multicells and a few supercells is expected, with large hail and severe gusts possible, while a tornado cannot be ruled out. As height falls and cooling/destabilization aloft spread across the warm sector, diurnal heating will further contribute to steepening deep-layer lapse rates, atop a plume of 60s F surface dew points near and west of the eastern frontal zone. Modified RAOBs and model soundings indicate that the peak MLCAPE -- behind the morning clouds/convection related to the initial perturbation -- should reach 2000-2500 J/kg, despite patchy cloud cover. 35-45 kt effective-shear magnitudes will support convective organization, as will strong upper-level/ventilating winds. Low-level flow will be modest and, in much of the area, veered west of southerly, limiting hodograph size. Overall weakening of convection is expected late evening into the overnight hours as remaining activity moves deeper into/atop a progressively more-stable boundary layer within and east of the slow-moving surface warm-frontal zone. In each outlook level, slightly more room as been allotted for this process to occur into northwestern MN. ...Southern Plains to Ozarks region... Isolated gusts near severe limits still may occur with ongoing convection moving southeastward from the END area over central OK, before it weakens. See SPC mesoscale discussion 1856 for additional near-term details. Otherwise, widely scattered to scattered thunderstorms are expected to develop through this afternoon over portions of the Ozarks and vicinity, amidst rich low-level moisture (70s F surface dew points, roughly 2-inch PW) and minimal MLCINH. Activity should be focused along and ahead of the outflow boundaries from the morning MCS activity over portions of KS/OK. A general westward increase in midlevel lapse rates, combined with surface diabatic heating and aforementioned moisture, should contribute to MLCAPE ranging from around 3500 J/kg over parts of eastern OK to 1000-1500 J/kg in the frontal zone across the Ozarks region. Although some large-scale support may be provided in the form of weak DCVA and/or mesobeta- scale midlevel gradient-flow enhancement around the MCV(s), overall organization of the convection should be loose and multicellular in nature given weak low-level shear and modest mid/upper winds in most of the region. Damaging to severe gusts are possible in strongly water-loaded downdrafts, but the unconditional severe threat appears isolated and marginal. ..Edwards/Gleason.. 08/25/2019 Read more

000
ABPZ20 KNHC 251140
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 AM PDT Sun Aug 25 2019

For the eastern North Pacific...east of 140 degrees west longitude:

The National Hurricane Center is issuing advisories on recently
downgraded Tropical Depression Ivo, located several hundred miles
west-northwest of the southern tip of the Baja California peninsula.

A trough of low pressure is forecast to develop in a couple of days
near the southern tip of the Baja California peninsula. Development
of this system into a tropical cyclone appears unlikely while the
system moves slowly westward or west-northwestward.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...low...near 0 percent.

$$
Forecaster Stewart

MD 1856 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF NORTHERN/CENTRAL OK
Mesoscale Discussion 1856 NWS Storm Prediction Center Norman OK 0636 AM CDT Sun Aug 25 2019 Areas affected...Portions of northern/central OK Concerning...Severe potential...Watch unlikely Valid 251136Z - 251330Z Probability of Watch Issuance...5 percent SUMMARY...An isolated strong/gusty wind threat may continue with a small cluster of storms for the next couple of hours. However, watch issuance is not expected. DISCUSSION...A 25-35 kt southwesterly low-level jet over the central and southern High Plains is expected to diurnally weaken over the next 2-3 hours. This will likely reduce low-level mass influx into a small cluster of storms located over part of northern OK at 1135Z. A gradual weakening trend should likewise occur with this convection as it continues to move southward into a convectively overturned airmass across central OK this morning. In the meantime, isolated wind gusts of 50-60 mph capable of occasional damage will remain possible. A gust to 56 mph was recorded at the Alva OK Mesonet site at 11Z. Given current expectations for gradual weakening and the overall isolated threat, Severe Thunderstorm Watch issuance is not currently anticipated for any portion of northern/central OK this morning. ..Gleason/Edwards.. 08/25/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...OUN... LAT...LON 36639887 36579833 36759794 36359756 35939731 35569719 35199741 34969777 34939832 35039875 35529912 36189913 36639887 Read more

WW 0618 Status Updates
STATUS REPORT ON WW 618 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 WNW RSL TO 20 SSW RSL TO 35 W HUT TO 10 NE P28 TO 25 ENE AVK. ..GLEASON..08/25/19 ATTN...WFO...DDC...ICT...TOP... STATUS REPORT FOR WS 618 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS KSC007-009-033-047-097-145-151-165-185-251140- KS . KANSAS COUNTIES INCLUDED ARE BARBER BARTON COMANCHE EDWARDS KIOWA PAWNEE PRATT RUSH STAFFORD THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more