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SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CDT Sun Sep 01 2019 Valid 011630Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS CENTRAL AND SOUTHERN ARIZONA... ...SUMMARY... Scattered severe wind gusts are possible across parts of central and southern Arizona during the late afternoon and evening, with other severe storms possible across the northern High Plains and Ohio Valley. ...Central/southern Arizona... The mid/upper-level ridge will remain centered over the Four Corners area through tonight, with a belt of moderately strong easterly mid-level winds on its immediate southern periphery as sampled by 12Z observed soundings from Phoenix/Tucson. Orographic lift will be the primary driver of isolated to widely scattered thunderstorms by early afternoon across the higher terrain of western New Mexico into central/eastern Arizona. With a belt of 15-25 kt easterlies across the southern half of Arizona, this convection will spread westward over the lower deserts during the late afternoon and evening. Surface dew points should mix into the upper 50s to mid 60s at peak heating across the Lower Colorado and Gila Valleys, yielding at least moderate buoyancy with MLCAPE above 1000 J/kg. One or two clusters may organize off the terrain with a risk for scattered severe-caliber wind gusts, with at least a couple of these storms likely to reach the Lower Colorado River Valley. ...Ohio Valley... A convectively influenced shortwave trough centered over central Indiana at late morning will continue east-northeastward toward the Upper Ohio Valley and western portions of Pennsylvania/New York. Modest ascent ahead of this feature will continue to influence thunderstorm development across the region, with some increase in coverage/intensity this afternoon as MLCAPE reaches 1000-1500 J/kg. The primary risks from multicell clusters should be isolated strong gusts and marginally severe hail. However, guidance is fairly consistent in strengthening low-level winds early this evening from the Upper Ohio Valley to northern Appalachians. A small temporal window may exist for a supercell-related brief tornado risk near the Ohio/Pennsylvania/West Virginia border area as low-level hodographs enlarge prior to surface-based instability decreasing with eastern extent in Pennsylvania. ...Northern High Plains including Montana to Nebraska... No changes warranted for the region. A mid-level ridge will remain prominent across much of the northern Great Plains through the period, although some flattening is anticipated towards 12Z/Monday as a vigorous shortwave trough amplifies over the Canadian Rockies. Isolated thunderstorms may develop along the lee trough from north-central Montana to the Nebraska/Colorado border area. Buoyancy will be weak to the northwest but may be compensated by plentiful mid to upper-level speed shear. A couple cells with mid-level updraft rotation may form but will likely struggle to be sustained eastward given pronounced MLCIN east of the trough. Have expanded/combined the MRGL risk areas to account for this scenario. Otherwise, an arc of 700-mb warm theta-e advection should yield isolated to perhaps scattered elevated thunderstorms overnight across eastern Montana and the Dakotas into Nebraska. Strongest speed shear will be across the northern portion of the region, with MUCAPE increasing as richer 850-mb moisture advects north. It is unclear whether uncapped parcels can become rooted beneath 700-mb prior to 12Z. For now, will maintain MRGL risk, mainly for the potential of isolated severe hail. ..Guyer/Nauslar.. 09/01/2019 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CDT Sun Sep 01 2019 Valid 011630Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS CENTRAL AND SOUTHERN ARIZONA... ...SUMMARY... Scattered severe wind gusts are possible across parts of central and southern Arizona during the late afternoon and evening, with other severe storms possible across the northern High Plains and Ohio Valley. ...Central/southern Arizona... The mid/upper-level ridge will remain centered over the Four Corners area through tonight, with a belt of moderately strong easterly mid-level winds on its immediate southern periphery as sampled by 12Z observed soundings from Phoenix/Tucson. Orographic lift will be the primary driver of isolated to widely scattered thunderstorms by early afternoon across the higher terrain of western New Mexico into central/eastern Arizona. With a belt of 15-25 kt easterlies across the southern half of Arizona, this convection will spread westward over the lower deserts during the late afternoon and evening. Surface dew points should mix into the upper 50s to mid 60s at peak heating across the Lower Colorado and Gila Valleys, yielding at least moderate buoyancy with MLCAPE above 1000 J/kg. One or two clusters may organize off the terrain with a risk for scattered severe-caliber wind gusts, with at least a couple of these storms likely to reach the Lower Colorado River Valley. ...Ohio Valley... A convectively influenced shortwave trough centered over central Indiana at late morning will continue east-northeastward toward the Upper Ohio Valley and western portions of Pennsylvania/New York. Modest ascent ahead of this feature will continue to influence thunderstorm development across the region, with some increase in coverage/intensity this afternoon as MLCAPE reaches 1000-1500 J/kg. The primary risks from multicell clusters should be isolated strong gusts and marginally severe hail. However, guidance is fairly consistent in strengthening low-level winds early this evening from the Upper Ohio Valley to northern Appalachians. A small temporal window may exist for a supercell-related brief tornado risk near the Ohio/Pennsylvania/West Virginia border area as low-level hodographs enlarge prior to surface-based instability decreasing with eastern extent in Pennsylvania. ...Northern High Plains including Montana to Nebraska... No changes warranted for the region. A mid-level ridge will remain prominent across much of the northern Great Plains through the period, although some flattening is anticipated towards 12Z/Monday as a vigorous shortwave trough amplifies over the Canadian Rockies. Isolated thunderstorms may develop along the lee trough from north-central Montana to the Nebraska/Colorado border area. Buoyancy will be weak to the northwest but may be compensated by plentiful mid to upper-level speed shear. A couple cells with mid-level updraft rotation may form but will likely struggle to be sustained eastward given pronounced MLCIN east of the trough. Have expanded/combined the MRGL risk areas to account for this scenario. Otherwise, an arc of 700-mb warm theta-e advection should yield isolated to perhaps scattered elevated thunderstorms overnight across eastern Montana and the Dakotas into Nebraska. Strongest speed shear will be across the northern portion of the region, with MUCAPE increasing as richer 850-mb moisture advects north. It is unclear whether uncapped parcels can become rooted beneath 700-mb prior to 12Z. For now, will maintain MRGL risk, mainly for the potential of isolated severe hail. ..Guyer/Nauslar.. 09/01/2019 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1049 AM CDT Sun Sep 01 2019 Valid 011700Z - 021200Z The current forecast remains on track, with only minimal changes needed with this forecast update to reflect observations and the latest model guidance. While a few HREFv2 members suggest at least some potential for elevated fire weather conditions this afternoon across portions of far north-central Colorado, recent precipitation (>0.5" over past 48 hours according to AHPS) and brief/spotty nature of any elevated meteorological conditions preclude expanding the elevated fire weather area into Colorado. Please see discussion below for more information on today's fire weather threat. ..Elliott.. 09/01/2019 .PREV DISCUSSION... /ISSUED 1241 AM CDT Sun Sep 01 2019/ ...Synopsis... An upper-level ridge will prevail across the western CONUS throughout the day, with an intensifying mid-level impulse beginning to crest the ridge, across the Pacific Northwest/northern Rockies regions by the end of the period. The resultant strengthening flow aloft by peak heating may be transported downward via a deep, mixed boundary layer, promoting dry and breezy conditions which may foster some threat for wildfire-spread. ...Northern Great Basin into the central Rockies... Downslope flow and boundary layer mixing of the winds aloft will result in 15-20 mph sustained west-southwesterly surface winds and 10-20% RH, from parts of the Snake River Plain into the Great Divide Basin. An elevated area has been maintained for regions where the aforementioned breezy, dry surface conditions are expected to persist for several hours during the afternoon. Fuels across this area are also quite supportive of wildfire-spread potential. Farther west-southwest into parts of the Great Basin, at least localized to briefly widespread elevated conditions may be observed, but the patchy or brief nature of such conditions precludes a delineation at this time. ...Central into southern Colorado and far northwest New Mexico... A couple of thunderstorms may initiate atop the higher terrain of the Rocky Mountains across parts of central Colorado into Northwest New Mexico during the afternoon hours. These storms may be high-based in nature, with a couple of dry strikes possible, and where fuels are marginally to modestly receptive to fire spread. The very sparse nature of dry strikes renders an isolated dry thunderstorm delineation unwarranted at this time. ...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 1049 AM CDT Sun Sep 01 2019 Valid 011700Z - 021200Z The current forecast remains on track, with only minimal changes needed with this forecast update to reflect observations and the latest model guidance. While a few HREFv2 members suggest at least some potential for elevated fire weather conditions this afternoon across portions of far north-central Colorado, recent precipitation (>0.5" over past 48 hours according to AHPS) and brief/spotty nature of any elevated meteorological conditions preclude expanding the elevated fire weather area into Colorado. Please see discussion below for more information on today's fire weather threat. ..Elliott.. 09/01/2019 .PREV DISCUSSION... /ISSUED 1241 AM CDT Sun Sep 01 2019/ ...Synopsis... An upper-level ridge will prevail across the western CONUS throughout the day, with an intensifying mid-level impulse beginning to crest the ridge, across the Pacific Northwest/northern Rockies regions by the end of the period. The resultant strengthening flow aloft by peak heating may be transported downward via a deep, mixed boundary layer, promoting dry and breezy conditions which may foster some threat for wildfire-spread. ...Northern Great Basin into the central Rockies... Downslope flow and boundary layer mixing of the winds aloft will result in 15-20 mph sustained west-southwesterly surface winds and 10-20% RH, from parts of the Snake River Plain into the Great Divide Basin. An elevated area has been maintained for regions where the aforementioned breezy, dry surface conditions are expected to persist for several hours during the afternoon. Fuels across this area are also quite supportive of wildfire-spread potential. Farther west-southwest into parts of the Great Basin, at least localized to briefly widespread elevated conditions may be observed, but the patchy or brief nature of such conditions precludes a delineation at this time. ...Central into southern Colorado and far northwest New Mexico... A couple of thunderstorms may initiate atop the higher terrain of the Rocky Mountains across parts of central Colorado into Northwest New Mexico during the afternoon hours. These storms may be high-based in nature, with a couple of dry strikes possible, and where fuels are marginally to modestly receptive to fire spread. The very sparse nature of dry strikes renders an isolated dry thunderstorm delineation unwarranted at this time. ...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 1049 AM CDT Sun Sep 01 2019 Valid 011700Z - 021200Z The current forecast remains on track, with only minimal changes needed with this forecast update to reflect observations and the latest model guidance. While a few HREFv2 members suggest at least some potential for elevated fire weather conditions this afternoon across portions of far north-central Colorado, recent precipitation (>0.5" over past 48 hours according to AHPS) and brief/spotty nature of any elevated meteorological conditions preclude expanding the elevated fire weather area into Colorado. Please see discussion below for more information on today's fire weather threat. ..Elliott.. 09/01/2019 .PREV DISCUSSION... /ISSUED 1241 AM CDT Sun Sep 01 2019/ ...Synopsis... An upper-level ridge will prevail across the western CONUS throughout the day, with an intensifying mid-level impulse beginning to crest the ridge, across the Pacific Northwest/northern Rockies regions by the end of the period. The resultant strengthening flow aloft by peak heating may be transported downward via a deep, mixed boundary layer, promoting dry and breezy conditions which may foster some threat for wildfire-spread. ...Northern Great Basin into the central Rockies... Downslope flow and boundary layer mixing of the winds aloft will result in 15-20 mph sustained west-southwesterly surface winds and 10-20% RH, from parts of the Snake River Plain into the Great Divide Basin. An elevated area has been maintained for regions where the aforementioned breezy, dry surface conditions are expected to persist for several hours during the afternoon. Fuels across this area are also quite supportive of wildfire-spread potential. Farther west-southwest into parts of the Great Basin, at least localized to briefly widespread elevated conditions may be observed, but the patchy or brief nature of such conditions precludes a delineation at this time. ...Central into southern Colorado and far northwest New Mexico... A couple of thunderstorms may initiate atop the higher terrain of the Rocky Mountains across parts of central Colorado into Northwest New Mexico during the afternoon hours. These storms may be high-based in nature, with a couple of dry strikes possible, and where fuels are marginally to modestly receptive to fire spread. The very sparse nature of dry strikes renders an isolated dry thunderstorm delineation unwarranted at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

5-Day Uncertainty Track last updated Sun, 01 Sep 2019 14:41:42 GMT


Wind Speed Probabilities last updated Sun, 01 Sep 2019 15:31:35 GMT

Issued at 900 AM MDT Sun Sep 01 2019 000 WTPZ41 KNHC 011441 TCDEP1 Tropical Storm Juliette Discussion Number 2 NWS National Hurricane Center Miami FL EP112019 900 AM MDT Sun Sep 01 2019 Juliette has been quickly organizing this morning. Satellite and microwave data indicate that a small central dense overcast has formed, with a large band on the east side. The current wind speed is set to 50 kt, in line with the recent CIMSS objective Dvorak estimate since the subjective estimates are still catching up with this storm. There's been a significant change to the intensity and size forecasts of Juliette this morning, with guidance now showing a stronger and larger hurricane in about a day. This is consistent with the recent development of the early stages of an inner core, which would allow Juliette to continue to intensify at a fast pace. Indeed, rapid intensification is a distinct possibility due to an environment of low shear and very warm water, and the various rapid intensification indices are all showing this chance. Thus the forecast is raised from the last one, similar to the corrected consensus guidance, and further upward adjustments might be required this afternoon. Fixes show that the storm is moving faster to the northwest this morning. A ridge to the northeast of Juliette should steer the storm on this general path for the next several days, followed by a slight turn toward the west-northwest at the end. Model guidance is in fairly good agreement on this scenario, and the new forecast is basically an update of the previous one, close to the eastern Pacific model consensus TVCE. FORECAST POSITIONS AND MAX WINDS INIT 01/1500Z 14.3N 108.8W 50 KT 60 MPH 12H 02/0000Z 15.3N 110.3W 60 KT 70 MPH 24H 02/1200Z 16.5N 112.3W 75 KT 85 MPH 36H 03/0000Z 17.4N 114.1W 85 KT 100 MPH 48H 03/1200Z 18.1N 115.6W 90 KT 105 MPH 72H 04/1200Z 19.2N 118.5W 75 KT 85 MPH 96H 05/1200Z 20.5N 121.8W 70 KT 80 MPH 120H 06/1200Z 22.5N 125.5W 60 KT 70 MPH $$ Forecaster Blake

Issued at 1500 UTC SUN SEP 01 2019 000 FOPZ11 KNHC 011440 PWSEP1 TROPICAL STORM JULIETTE WIND SPEED PROBABILITIES NUMBER 2 NWS NATIONAL HURRICANE CENTER MIAMI FL EP112019 1500 UTC SUN SEP 01 2019 AT 1500Z THE CENTER OF TROPICAL STORM JULIETTE WAS LOCATED NEAR LATITUDE 14.3 NORTH...LONGITUDE 108.8 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 50 KTS...60 MPH...95 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 15N 110W 34 95 2(97) X(97) X(97) X(97) X(97) X(97) 15N 110W 50 41 7(48) X(48) X(48) X(48) X(48) X(48) 15N 110W 64 8 2(10) X(10) X(10) X(10) X(10) X(10) 20N 110W 34 1 3( 4) 3( 7) 1( 8) X( 8) X( 8) X( 8) ISLA SOCORRO 34 2 11(13) 6(19) 2(21) 1(22) X(22) X(22) ISLA CLARION 34 X 7( 7) 57(64) 23(87) 2(89) 1(90) X(90) ISLA CLARION 50 X X( X) 19(19) 37(56) 4(60) X(60) X(60) ISLA CLARION 64 X X( X) 5( 5) 29(34) 3(37) X(37) X(37) 15N 115W 34 1 4( 5) 12(17) 6(23) 3(26) X(26) X(26) 15N 115W 50 X X( X) 2( 2) X( 2) 1( 3) X( 3) X( 3) 20N 115W 34 X 3( 3) 13(16) 27(43) 11(54) 1(55) X(55) 20N 115W 50 X X( X) 1( 1) 6( 7) 6(13) X(13) X(13) 20N 115W 64 X X( X) X( X) 2( 2) 2( 4) X( 4) X( 4) 15N 120W 34 X X( X) X( X) 1( 1) 6( 7) 2( 9) 1(10) 20N 120W 34 X X( X) X( X) 3( 3) 33(36) 36(72) 4(76) 20N 120W 50 X X( X) X( X) X( X) 8( 8) 27(35) 1(36) 20N 120W 64 X X( X) X( X) X( X) 3( 3) 14(17) 1(18) 25N 120W 34 X X( X) X( X) X( X) X( X) 4( 4) 2( 6) 20N 125W 34 X X( X) X( X) X( X) X( X) 12(12) 22(34) 20N 125W 50 X X( X) X( X) X( X) X( X) 2( 2) 10(12) 20N 125W 64 X X( X) X( X) X( X) X( X) 1( 1) 3( 4) 25N 125W 34 X X( X) X( X) X( X) X( X) 2( 2) 16(18) 25N 125W 50 X X( X) X( X) X( X) X( X) X( X) 3( 3) 20N 130W 34 X X( X) X( X) X( X) X( X) X( X) 4( 4) 25N 130W 34 X X( X) X( X) X( X) X( X) X( X) 4( 4) $$ FORECASTER BLAKE

Issued at 1500 UTC SUN SEP 01 2019 000 WTPZ21 KNHC 011440 TCMEP1 TROPICAL STORM JULIETTE FORECAST/ADVISORY NUMBER 2 NWS NATIONAL HURRICANE CENTER MIAMI FL EP112019 1500 UTC SUN SEP 01 2019 THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT. TROPICAL STORM CENTER LOCATED NEAR 14.3N 108.8W AT 01/1500Z POSITION ACCURATE WITHIN 25 NM PRESENT MOVEMENT TOWARD THE NORTHWEST OR 315 DEGREES AT 12 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1000 MB MAX SUSTAINED WINDS 50 KT WITH GUSTS TO 60 KT. 50 KT....... 30NE 0SE 0SW 0NW. 34 KT....... 70NE 60SE 20SW 60NW. 12 FT SEAS..120NE 60SE 20SW 60NW. 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 14.3N 108.8W AT 01/1500Z AT 01/1200Z CENTER WAS LOCATED NEAR 13.9N 108.2W FORECAST VALID 02/0000Z 15.3N 110.3W MAX WIND 60 KT...GUSTS 75 KT. 50 KT... 40NE 30SE 30SW 40NW. 34 KT... 90NE 70SE 40SW 80NW. FORECAST VALID 02/1200Z 16.5N 112.3W MAX WIND 75 KT...GUSTS 90 KT. 64 KT... 30NE 20SE 15SW 20NW. 50 KT... 60NE 50SE 40SW 50NW. 34 KT...110NE 90SE 70SW 100NW. FORECAST VALID 03/0000Z 17.4N 114.1W MAX WIND 85 KT...GUSTS 105 KT. 64 KT... 40NE 25SE 25SW 30NW. 50 KT... 60NE 50SE 50SW 60NW. 34 KT...120NE 100SE 80SW 110NW. FORECAST VALID 03/1200Z 18.1N 115.6W MAX WIND 90 KT...GUSTS 110 KT. 64 KT... 40NE 35SE 35SW 40NW. 50 KT... 60NE 50SE 50SW 60NW. 34 KT...120NE 100SE 80SW 110NW. FORECAST VALID 04/1200Z 19.2N 118.5W MAX WIND 75 KT...GUSTS 90 KT. 50 KT... 60NE 50SE 50SW 60NW. 34 KT...120NE 90SE 80SW 110NW. EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 100 NM ON DAY 4 AND 150 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY OUTLOOK VALID 05/1200Z 20.5N 121.8W MAX WIND 70 KT...GUSTS 85 KT. OUTLOOK VALID 06/1200Z 22.5N 125.5W MAX WIND 60 KT...GUSTS 75 KT. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 14.3N 108.8W NEXT ADVISORY AT 01/2100Z $$ FORECASTER BLAKE

Issued at 900 AM MDT Sun Sep 01 2019 000 WTPZ31 KNHC 011440 TCPEP1 BULLETIN Tropical Storm Juliette Advisory Number 2 NWS National Hurricane Center Miami FL EP112019 900 AM MDT Sun Sep 01 2019 ...JULIETTE STRENGTHENING QUICKLY WELL SOUTHWEST OF MEXICO... SUMMARY OF 900 AM MDT...1500 UTC...INFORMATION ---------------------------------------------- LOCATION...14.3N 108.8W ABOUT 440 MI...710 KM SW OF MANZANILLO MEXICO ABOUT 600 MI...965 KM S OF THE SOUTHERN TIP OF BAJA CALIFORNIA MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/H PRESENT MOVEMENT...NW OR 315 DEGREES AT 14 MPH...22 KM/H MINIMUM CENTRAL PRESSURE...1000 MB...29.53 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 900 AM MDT (1500 UTC), the center of Tropical Storm Juliette was located near latitude 14.3 North, longitude 108.8 West. Juliette is moving toward the northwest near 14 mph (22 km/h), and this general motion is expected to continue today. A turn toward the west- northwest with an increase in forward speed is expected by Monday and this general motion is forecast through Wednesday. Maximum sustained winds have increased to near 60 mph (95 km/h) with higher gusts. Juliette is expected to become a hurricane tomorrow and continue to intensify on Tuesday. Weakening could begin on Wednesday. Tropical-storm-force winds extend outward up to 80 miles (130 km) from the center. The estimated minimum central pressure is 1000 mb (29.53 inches). HAZARDS AFFECTING LAND ---------------------- None. NEXT ADVISORY ------------- Next complete advisory at 300 PM MDT. $$ Forecaster Blake

...JULIETTE STRENGTHENING QUICKLY WELL SOUTHWEST OF MEXICO... As of 9:00 AM MDT Sun Sep 1 the center of Juliette was located near 14.3, -108.8 with movement NW at 14 mph. The minimum central pressure was 1000 mb with maximum sustained winds of about 60 mph.

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0750 AM CDT Sun Sep 01 2019 Valid 011300Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS CENTRAL AND SOUTHERN AZ... ...SUMMARY... Scattered severe wind gusts are possible across parts of central and southern Arizona during the late afternoon and evening. ...Central/southern Arizona... A stout mid-level anticyclone will remain centered over the Four Corners area. Orographic lift will be the primary driver of isolated to widely scattered thunderstorms by early afternoon across the higher terrain of western NM into eastern AZ. With a belt of 15-25 kt easterlies across the southern half of AZ, this convection will spread west over the lower deserts during the late afternoon and evening. Surface dew points should mix into the upper 50s to mid 60s at peak heating across the Lower Colorado and Gila Valleys, yielding at least moderate buoyancy with MLCAPE above 1000 J/kg. One or two clusters may organize off the terrain with a risk for scattered severe wind gusts until convection weakens overnight amid increasingly substantial MLCIN in the Mojave Desert. ...OH Valley... Within broadly cyclonic flow over eastern Canada and the Great Lakes, a minor shortwave impulse will eject east from IL towards PA/NY. Modest ascent ahead of this feature has encouraged a couple thunderstorm clusters from central IL to Lower MI and over the Upper OH Valley. This activity should remain weak through midday, but will likely increase in coverage and intensity this afternoon as MLCAPE reaches 1000-1500 J/kg across parts of IN/OH ahead of the IL cluster. The primary risks from multicell clusters should be isolated strong gusts and marginally severe hail. However, guidance is fairly consistent in strengthening low-level winds this evening from the Upper OH Valley to northern Appalachians. A small temporal window should exist for a brief tornado risk near the OH/PA/WV border area as low-level hodographs enlarge prior to surface-based instability decreasing with eastern extent in PA. ...MT to NE... A mid-level ridge will remain prominent across much of the northern Great Plains through the period, although some flattening is anticipated towards 12Z/Monday as a vigorous shortwave trough amplifies over the Canadian Rockies. Considerable uncertainty remains regarding possible convective initiation during the late afternoon and early evening. Isolated thunderstorms may develop along the lee trough from north-central MT to the NE/CO border area. Buoyancy will be weak to the northwest but may be compensated by plentiful mid to upper-level speed shear. A couple cells with mid-level updraft rotation may form but will likely struggle to be sustained eastward given pronounced MLCIN east of the trough. Have expanded/combined the MRGL risk areas to account for this scenario. Otherwise, an arc of 700-mb warm theta-e advection should yield isolated to perhaps scattered elevated thunderstorms overnight across eastern MT and the Dakotas into NE. Strongest speed shear will be across the northern portion of the region, with MUCAPE increasing as richer 850-mb moisture advects north. It is unclear whether uncapped parcels can become rooted beneath 700-mb prior to 12Z. For now, will maintain MRGL risk, mainly for the potential of isolated severe hail. ..Grams/Leitman.. 09/01/2019 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0750 AM CDT Sun Sep 01 2019 Valid 011300Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS CENTRAL AND SOUTHERN AZ... ...SUMMARY... Scattered severe wind gusts are possible across parts of central and southern Arizona during the late afternoon and evening. ...Central/southern Arizona... A stout mid-level anticyclone will remain centered over the Four Corners area. Orographic lift will be the primary driver of isolated to widely scattered thunderstorms by early afternoon across the higher terrain of western NM into eastern AZ. With a belt of 15-25 kt easterlies across the southern half of AZ, this convection will spread west over the lower deserts during the late afternoon and evening. Surface dew points should mix into the upper 50s to mid 60s at peak heating across the Lower Colorado and Gila Valleys, yielding at least moderate buoyancy with MLCAPE above 1000 J/kg. One or two clusters may organize off the terrain with a risk for scattered severe wind gusts until convection weakens overnight amid increasingly substantial MLCIN in the Mojave Desert. ...OH Valley... Within broadly cyclonic flow over eastern Canada and the Great Lakes, a minor shortwave impulse will eject east from IL towards PA/NY. Modest ascent ahead of this feature has encouraged a couple thunderstorm clusters from central IL to Lower MI and over the Upper OH Valley. This activity should remain weak through midday, but will likely increase in coverage and intensity this afternoon as MLCAPE reaches 1000-1500 J/kg across parts of IN/OH ahead of the IL cluster. The primary risks from multicell clusters should be isolated strong gusts and marginally severe hail. However, guidance is fairly consistent in strengthening low-level winds this evening from the Upper OH Valley to northern Appalachians. A small temporal window should exist for a brief tornado risk near the OH/PA/WV border area as low-level hodographs enlarge prior to surface-based instability decreasing with eastern extent in PA. ...MT to NE... A mid-level ridge will remain prominent across much of the northern Great Plains through the period, although some flattening is anticipated towards 12Z/Monday as a vigorous shortwave trough amplifies over the Canadian Rockies. Considerable uncertainty remains regarding possible convective initiation during the late afternoon and early evening. Isolated thunderstorms may develop along the lee trough from north-central MT to the NE/CO border area. Buoyancy will be weak to the northwest but may be compensated by plentiful mid to upper-level speed shear. A couple cells with mid-level updraft rotation may form but will likely struggle to be sustained eastward given pronounced MLCIN east of the trough. Have expanded/combined the MRGL risk areas to account for this scenario. Otherwise, an arc of 700-mb warm theta-e advection should yield isolated to perhaps scattered elevated thunderstorms overnight across eastern MT and the Dakotas into NE. Strongest speed shear will be across the northern portion of the region, with MUCAPE increasing as richer 850-mb moisture advects north. It is unclear whether uncapped parcels can become rooted beneath 700-mb prior to 12Z. For now, will maintain MRGL risk, mainly for the potential of isolated severe hail. ..Grams/Leitman.. 09/01/2019 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0750 AM CDT Sun Sep 01 2019 Valid 011300Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS CENTRAL AND SOUTHERN AZ... ...SUMMARY... Scattered severe wind gusts are possible across parts of central and southern Arizona during the late afternoon and evening. ...Central/southern Arizona... A stout mid-level anticyclone will remain centered over the Four Corners area. Orographic lift will be the primary driver of isolated to widely scattered thunderstorms by early afternoon across the higher terrain of western NM into eastern AZ. With a belt of 15-25 kt easterlies across the southern half of AZ, this convection will spread west over the lower deserts during the late afternoon and evening. Surface dew points should mix into the upper 50s to mid 60s at peak heating across the Lower Colorado and Gila Valleys, yielding at least moderate buoyancy with MLCAPE above 1000 J/kg. One or two clusters may organize off the terrain with a risk for scattered severe wind gusts until convection weakens overnight amid increasingly substantial MLCIN in the Mojave Desert. ...OH Valley... Within broadly cyclonic flow over eastern Canada and the Great Lakes, a minor shortwave impulse will eject east from IL towards PA/NY. Modest ascent ahead of this feature has encouraged a couple thunderstorm clusters from central IL to Lower MI and over the Upper OH Valley. This activity should remain weak through midday, but will likely increase in coverage and intensity this afternoon as MLCAPE reaches 1000-1500 J/kg across parts of IN/OH ahead of the IL cluster. The primary risks from multicell clusters should be isolated strong gusts and marginally severe hail. However, guidance is fairly consistent in strengthening low-level winds this evening from the Upper OH Valley to northern Appalachians. A small temporal window should exist for a brief tornado risk near the OH/PA/WV border area as low-level hodographs enlarge prior to surface-based instability decreasing with eastern extent in PA. ...MT to NE... A mid-level ridge will remain prominent across much of the northern Great Plains through the period, although some flattening is anticipated towards 12Z/Monday as a vigorous shortwave trough amplifies over the Canadian Rockies. Considerable uncertainty remains regarding possible convective initiation during the late afternoon and early evening. Isolated thunderstorms may develop along the lee trough from north-central MT to the NE/CO border area. Buoyancy will be weak to the northwest but may be compensated by plentiful mid to upper-level speed shear. A couple cells with mid-level updraft rotation may form but will likely struggle to be sustained eastward given pronounced MLCIN east of the trough. Have expanded/combined the MRGL risk areas to account for this scenario. Otherwise, an arc of 700-mb warm theta-e advection should yield isolated to perhaps scattered elevated thunderstorms overnight across eastern MT and the Dakotas into NE. Strongest speed shear will be across the northern portion of the region, with MUCAPE increasing as richer 850-mb moisture advects north. It is unclear whether uncapped parcels can become rooted beneath 700-mb prior to 12Z. For now, will maintain MRGL risk, mainly for the potential of isolated severe hail. ..Grams/Leitman.. 09/01/2019 Read more

000
ABPZ20 KNHC 011141
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 AM PDT Sun Sep 1 2019

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

The National Hurricane Center is issuing advisories on newly formed
Tropical Storm Juliette, located several hundred miles
south-southwest of Mexico.

Tropical cyclone formation is not expected during the next 5 days.

&&

Public Advisories on Juliette are issued under WMO header WTPZ31
KNHC and under AWIPS header MIATCPEP1.
Forecast/Advisories on Juliette are issued under WMO header WTPZ21
KNHC and under AWIPS header MIATCMEP1.

$$
Forecaster Blake

5-Day Uncertainty Track last updated Sun, 01 Sep 2019 08:33:40 GMT


Wind Speed Probabilities last updated Sun, 01 Sep 2019 09:31:49 GMT

Issued at 0900 UTC SUN SEP 01 2019 000 FOPZ11 KNHC 010832 PWSEP1 TROPICAL STORM JULIETTE WIND SPEED PROBABILITIES NUMBER 1 NWS NATIONAL HURRICANE CENTER MIAMI FL EP112019 0900 UTC SUN SEP 01 2019 AT 0900Z THE CENTER OF TROPICAL STORM JULIETTE WAS LOCATED NEAR LATITUDE 13.2 NORTH...LONGITUDE 107.6 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 40 KTS...45 MPH...75 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 06Z 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 06Z SUN 18Z SUN 06Z MON 18Z MON 06Z TUE 06Z WED 06Z THU PERIODS TO TO TO TO TO TO TO 18Z SUN 06Z MON 18Z MON 06Z TUE 06Z WED 06Z THU 06Z FRI FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT 15N 110W 34 51 34(85) X(85) X(85) X(85) X(85) X(85) 15N 110W 50 4 26(30) 1(31) X(31) X(31) X(31) X(31) 15N 110W 64 X 3( 3) X( 3) X( 3) X( 3) X( 3) X( 3) 20N 110W 34 X 2( 2) 3( 5) 1( 6) 1( 7) X( 7) X( 7) ISLA SOCORRO 34 X 5( 5) 7(12) 4(16) 1(17) X(17) X(17) ISLA CLARION 34 X 2( 2) 25(27) 46(73) 8(81) 1(82) X(82) ISLA CLARION 50 X X( X) 2( 2) 30(32) 9(41) X(41) X(41) ISLA CLARION 64 X X( X) X( X) 13(13) 6(19) X(19) X(19) 15N 115W 34 X 3( 3) 14(17) 10(27) 3(30) 1(31) X(31) 15N 115W 50 X X( X) 1( 1) 3( 4) X( 4) X( 4) X( 4) 20N 115W 34 X X( X) 7( 7) 18(25) 18(43) 2(45) X(45) 20N 115W 50 X X( X) X( X) 2( 2) 6( 8) X( 8) X( 8) 20N 115W 64 X X( X) X( X) X( X) 3( 3) X( 3) X( 3) 15N 120W 34 X X( X) X( X) 1( 1) 5( 6) 5(11) X(11) 20N 120W 34 X X( X) X( X) 1( 1) 24(25) 40(65) 6(71) 20N 120W 50 X X( X) X( X) X( X) 3( 3) 27(30) 4(34) 20N 120W 64 X X( X) X( X) X( X) 2( 2) 12(14) 2(16) 25N 120W 34 X X( X) X( X) X( X) X( X) 3( 3) 2( 5) 20N 125W 34 X X( X) X( X) X( X) X( X) 7( 7) 23(30) 20N 125W 50 X X( X) X( X) X( X) X( X) 2( 2) 7( 9) 20N 125W 64 X X( X) X( X) X( X) X( X) X( X) 3( 3) 25N 125W 34 X X( X) X( X) X( X) X( X) 1( 1) 8( 9) 20N 130W 34 X X( X) X( X) X( X) X( X) X( X) 3( 3) $$ FORECASTER STEWART

Issued at 300 AM MDT Sun Sep 01 2019 000 WTPZ41 KNHC 010832 TCDEP1 Tropical Storm Juliette Discussion Number 1 NWS National Hurricane Center Miami FL EP112019 300 AM MDT Sun Sep 01 2019 Earlier scatterometer surface wind data around 0400 UTC indicate that the low pressure system located about 400 nmi south-southwest of Manzanillo, Mexico, had become better defined and that tropical-storm-force winds were occurring in the northern semicircle. More specifically, an ASCAT-A pass revealed peak surface winds of 42 kt, which could have been slightly rain inflated, and an ASCAT-C pass showed peak winds of 39 kt. Based on a blend of these wind data, the low has been upgraded to a 40-kt tropical storm, the tenth tropical storm of the 2019 eastern North Pacific hurricane season. Juliette's initial motion estimate is an uncertain 310/06 kt. The advisory position is an average of the locations of the mid- and low-level circulation centers, in anticipation of the low-level center noted in the ASCAT-C wind data developing closer to the recent bursts of central deep convection. Otherwise, the track forecast is pretty straight-forward with the NHC model guidance in good agreement on maintaining the deep-layer ridge to the north of Juliette throughout the forecast period. This steering pattern should result in the cyclone moving slowly northwestward today, followed by a turn toward the west-northwest with an increase in forward speed on Monday, with a west-northwestward motion continuing through 120 hours. The NHC forecast track lies close to the tightly packed consensus models HCCA and TVCE. Juliette is expected to remain within a favorable environment for intensification to occur over the next 48-72 hours or so, which is characterized by low vertical wind shear of less than 10 kt, a moist mid-level environment, and sea-surface temperatures (SST) of 28-29 deg C. Therefore, the official intensity forecast calls for steady strengthening, with Juliette expected to become a hurricane on Monday. By 96 hours, the cyclone will be moving over SSTs around 26 deg C and cooler, which should induce gradual weakening. The NHC intensity forecast is above the consensus intensity models HCCA and IVCN, and is close to a blend of the statistical SHIPS intensity models and the dynamical HWRF model. FORECAST POSITIONS AND MAX WINDS INIT 01/0900Z 13.2N 107.6W 40 KT 45 MPH 12H 01/1800Z 14.5N 109.4W 45 KT 50 MPH 24H 02/0600Z 15.7N 111.5W 55 KT 65 MPH 36H 02/1800Z 16.7N 113.5W 65 KT 75 MPH 48H 03/0600Z 17.6N 115.2W 75 KT 85 MPH 72H 04/0600Z 18.9N 118.0W 75 KT 85 MPH 96H 05/0600Z 20.0N 121.0W 70 KT 80 MPH 120H 06/0600Z 21.8N 124.8W 55 KT 65 MPH $$ Forecaster Stewart

Issued at 0900 UTC SUN SEP 01 2019 000 WTPZ21 KNHC 010831 TCMEP1 TROPICAL STORM JULIETTE FORECAST/ADVISORY NUMBER 1 NWS NATIONAL HURRICANE CENTER MIAMI FL EP112019 0900 UTC SUN SEP 01 2019 THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT. TROPICAL STORM CENTER LOCATED NEAR 13.2N 107.6W AT 01/0900Z POSITION ACCURATE WITHIN 25 NM PRESENT MOVEMENT TOWARD THE NORTHWEST OR 310 DEGREES AT 6 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1004 MB MAX SUSTAINED WINDS 40 KT WITH GUSTS TO 50 KT. 34 KT....... 70NE 0SE 0SW 60NW. 12 FT SEAS.. 75NE 0SE 0SW 0NW. 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 13.2N 107.6W AT 01/0900Z AT 01/0600Z CENTER WAS LOCATED NEAR 13.0N 107.4W FORECAST VALID 01/1800Z 14.5N 109.4W MAX WIND 45 KT...GUSTS 55 KT. 34 KT... 70NE 50SE 0SW 60NW. FORECAST VALID 02/0600Z 15.7N 111.5W MAX WIND 55 KT...GUSTS 65 KT. 50 KT... 20NE 0SE 0SW 20NW. 34 KT... 70NE 50SE 0SW 60NW. FORECAST VALID 02/1800Z 16.7N 113.5W MAX WIND 65 KT...GUSTS 80 KT. 64 KT... 15NE 0SE 0SW 15NW. 50 KT... 30NE 20SE 0SW 30NW. 34 KT... 70NE 50SE 40SW 60NW. FORECAST VALID 03/0600Z 17.6N 115.2W MAX WIND 75 KT...GUSTS 90 KT. 64 KT... 15NE 0SE 0SW 15NW. 50 KT... 30NE 20SE 0SW 30NW. 34 KT... 70NE 50SE 40SW 60NW. FORECAST VALID 04/0600Z 18.9N 118.0W MAX WIND 75 KT...GUSTS 90 KT. 50 KT... 40NE 30SE 20SW 40NW. 34 KT... 90NE 70SE 50SW 80NW. EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 100 NM ON DAY 4 AND 150 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY OUTLOOK VALID 05/0600Z 20.0N 121.0W MAX WIND 70 KT...GUSTS 85 KT. OUTLOOK VALID 06/0600Z 21.8N 124.8W MAX WIND 55 KT...GUSTS 65 KT. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 13.2N 107.6W NEXT ADVISORY AT 01/1500Z $$ FORECASTER STEWART