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SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1250 AM CDT Mon Sep 01 2025 Valid 021200Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS INTO THE UPPER MIDWEST... ...SUMMARY... Isolated severe thunderstorms are possible across parts of the northern Plains into the Upper Midwest tomorrow (Tuesday). ...Synopsis... Broad cyclonic mid-level flow will persist along the Eastern Seaboard while upper ridging continues west of the Rockies, with the central U.S. placed under a northwesterly upper-flow regime tomorrow (Tuesday). A large and pronounced embedded mid-level shortwave will quickly translate southeastward from Canada and overspread the Upper MS Valley through the day, encouraging a surface cold front to surge southward across the northern Plains and Upper Midwest. Thunderstorms will develop ahead of the cold front, a few of which may be severe. ...Northern Plains into the Upper Midwest... Preceding the cold front will be a warm and seasonally moist airmass, overspread by 6.5-7.5 C/km mid-level lapse rates, yielding MLCAPE peaking in the 1500-2000 J/kg range by afternoon. Strengthening northwest flow with height will also yield modestly curved and elongated hodographs and 35+ kts of speed/effective bulk shear. These conditions will favor the development of multicells and perhaps a transient supercell with the stronger updrafts that manage to form ahead of the cold front. Isolated severe gusts or instances of hail are plausible, warranting the introduction of Category 1/Marginal risk severe probabilities this outlook. ..Squitieri.. 09/01/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1250 AM CDT Mon Sep 01 2025 Valid 021200Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS INTO THE UPPER MIDWEST... ...SUMMARY... Isolated severe thunderstorms are possible across parts of the northern Plains into the Upper Midwest tomorrow (Tuesday). ...Synopsis... Broad cyclonic mid-level flow will persist along the Eastern Seaboard while upper ridging continues west of the Rockies, with the central U.S. placed under a northwesterly upper-flow regime tomorrow (Tuesday). A large and pronounced embedded mid-level shortwave will quickly translate southeastward from Canada and overspread the Upper MS Valley through the day, encouraging a surface cold front to surge southward across the northern Plains and Upper Midwest. Thunderstorms will develop ahead of the cold front, a few of which may be severe. ...Northern Plains into the Upper Midwest... Preceding the cold front will be a warm and seasonally moist airmass, overspread by 6.5-7.5 C/km mid-level lapse rates, yielding MLCAPE peaking in the 1500-2000 J/kg range by afternoon. Strengthening northwest flow with height will also yield modestly curved and elongated hodographs and 35+ kts of speed/effective bulk shear. These conditions will favor the development of multicells and perhaps a transient supercell with the stronger updrafts that manage to form ahead of the cold front. Isolated severe gusts or instances of hail are plausible, warranting the introduction of Category 1/Marginal risk severe probabilities this outlook. ..Squitieri.. 09/01/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1238 AM CDT Mon Sep 01 2025 Valid 011200Z - 021200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The severe potential appears relatively low today across the continental U.S., though a few strong storms will be possible across parts of the Great Plains. ...DISCUSSION... At mid-levels, a ridge will be in place across the western U.S., with northwesterly flow located from the Rockies eastward to the Appalachians. A north-to-south corridor of low-level moisture will present in the Great Plains, where warming surface heating will contribute to scattered convective initiation. Throughout this airmass, surface dewpoints will be mostly in the 60s with weak instability developing by afternoon. Minimal deep-layer shear, poor lapse rates and a lack of large-scale ascent will limit the severe weather potential. Further west into the Pacific Northwest, a mid-level low will remain offshore from the Washington Coast. An axis of instability will develop across western Washington during the day. Isolated thunderstorms will be possible in the afternoon, but the environment should be insufficient for severe storms. Elsewhere across the continental United States, no severe threat is expected. ..Broyles/Moore.. 09/01/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1238 AM CDT Mon Sep 01 2025 Valid 011200Z - 021200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The severe potential appears relatively low today across the continental U.S., though a few strong storms will be possible across parts of the Great Plains. ...DISCUSSION... At mid-levels, a ridge will be in place across the western U.S., with northwesterly flow located from the Rockies eastward to the Appalachians. A north-to-south corridor of low-level moisture will present in the Great Plains, where warming surface heating will contribute to scattered convective initiation. Throughout this airmass, surface dewpoints will be mostly in the 60s with weak instability developing by afternoon. Minimal deep-layer shear, poor lapse rates and a lack of large-scale ascent will limit the severe weather potential. Further west into the Pacific Northwest, a mid-level low will remain offshore from the Washington Coast. An axis of instability will develop across western Washington during the day. Isolated thunderstorms will be possible in the afternoon, but the environment should be insufficient for severe storms. Elsewhere across the continental United States, no severe threat is expected. ..Broyles/Moore.. 09/01/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1238 AM CDT Mon Sep 01 2025 Valid 011200Z - 021200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The severe potential appears relatively low today across the continental U.S., though a few strong storms will be possible across parts of the Great Plains. ...DISCUSSION... At mid-levels, a ridge will be in place across the western U.S., with northwesterly flow located from the Rockies eastward to the Appalachians. A north-to-south corridor of low-level moisture will present in the Great Plains, where warming surface heating will contribute to scattered convective initiation. Throughout this airmass, surface dewpoints will be mostly in the 60s with weak instability developing by afternoon. Minimal deep-layer shear, poor lapse rates and a lack of large-scale ascent will limit the severe weather potential. Further west into the Pacific Northwest, a mid-level low will remain offshore from the Washington Coast. An axis of instability will develop across western Washington during the day. Isolated thunderstorms will be possible in the afternoon, but the environment should be insufficient for severe storms. Elsewhere across the continental United States, no severe threat is expected. ..Broyles/Moore.. 09/01/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1238 AM CDT Mon Sep 01 2025 Valid 011200Z - 021200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The severe potential appears relatively low today across the continental U.S., though a few strong storms will be possible across parts of the Great Plains. ...DISCUSSION... At mid-levels, a ridge will be in place across the western U.S., with northwesterly flow located from the Rockies eastward to the Appalachians. A north-to-south corridor of low-level moisture will present in the Great Plains, where warming surface heating will contribute to scattered convective initiation. Throughout this airmass, surface dewpoints will be mostly in the 60s with weak instability developing by afternoon. Minimal deep-layer shear, poor lapse rates and a lack of large-scale ascent will limit the severe weather potential. Further west into the Pacific Northwest, a mid-level low will remain offshore from the Washington Coast. An axis of instability will develop across western Washington during the day. Isolated thunderstorms will be possible in the afternoon, but the environment should be insufficient for severe storms. Elsewhere across the continental United States, no severe threat is expected. ..Broyles/Moore.. 09/01/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1238 AM CDT Mon Sep 01 2025 Valid 011200Z - 021200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The severe potential appears relatively low today across the continental U.S., though a few strong storms will be possible across parts of the Great Plains. ...DISCUSSION... At mid-levels, a ridge will be in place across the western U.S., with northwesterly flow located from the Rockies eastward to the Appalachians. A north-to-south corridor of low-level moisture will present in the Great Plains, where warming surface heating will contribute to scattered convective initiation. Throughout this airmass, surface dewpoints will be mostly in the 60s with weak instability developing by afternoon. Minimal deep-layer shear, poor lapse rates and a lack of large-scale ascent will limit the severe weather potential. Further west into the Pacific Northwest, a mid-level low will remain offshore from the Washington Coast. An axis of instability will develop across western Washington during the day. Isolated thunderstorms will be possible in the afternoon, but the environment should be insufficient for severe storms. Elsewhere across the continental United States, no severe threat is expected. ..Broyles/Moore.. 09/01/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1238 AM CDT Mon Sep 01 2025 Valid 011200Z - 021200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The severe potential appears relatively low today across the continental U.S., though a few strong storms will be possible across parts of the Great Plains. ...DISCUSSION... At mid-levels, a ridge will be in place across the western U.S., with northwesterly flow located from the Rockies eastward to the Appalachians. A north-to-south corridor of low-level moisture will present in the Great Plains, where warming surface heating will contribute to scattered convective initiation. Throughout this airmass, surface dewpoints will be mostly in the 60s with weak instability developing by afternoon. Minimal deep-layer shear, poor lapse rates and a lack of large-scale ascent will limit the severe weather potential. Further west into the Pacific Northwest, a mid-level low will remain offshore from the Washington Coast. An axis of instability will develop across western Washington during the day. Isolated thunderstorms will be possible in the afternoon, but the environment should be insufficient for severe storms. Elsewhere across the continental United States, no severe threat is expected. ..Broyles/Moore.. 09/01/2025 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1216 AM CDT Mon Sep 01 2025 Valid 021200Z - 031200Z ...Synopsis... The primary fire weather concern for Tuesday will be the potential for isolated dry thunderstorms across portions of northern CA into portions of northwest NV and central OR. Recent water-vapor imagery depicts a weak upper low off the southern CA coast that is forecast to meander northward over the next 48 hours. As this occurs, lift and mid-level moistening ahead of the wave will promote sufficient destabilization for convection beginning as early as 12z Tuesday morning across central CA, spreading northward through the afternoon and evening. In general, mid-level moisture quality should decrease with northward extent on the fringes of the better monsoonal moisture. An ensemble of forecast soundings suggests PWAT values may range from 0.6 to 0.8 inches across northern CA/northwest NV/central OR, which should favor a mix of wet and dry thunderstorms. Forecast storm motions between 15-20 knots may also help promote isolated dry lightning strikes over a landscape with ERCs between the 80th to 95th percentiles. ..Moore.. 09/01/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1216 AM CDT Mon Sep 01 2025 Valid 021200Z - 031200Z ...Synopsis... The primary fire weather concern for Tuesday will be the potential for isolated dry thunderstorms across portions of northern CA into portions of northwest NV and central OR. Recent water-vapor imagery depicts a weak upper low off the southern CA coast that is forecast to meander northward over the next 48 hours. As this occurs, lift and mid-level moistening ahead of the wave will promote sufficient destabilization for convection beginning as early as 12z Tuesday morning across central CA, spreading northward through the afternoon and evening. In general, mid-level moisture quality should decrease with northward extent on the fringes of the better monsoonal moisture. An ensemble of forecast soundings suggests PWAT values may range from 0.6 to 0.8 inches across northern CA/northwest NV/central OR, which should favor a mix of wet and dry thunderstorms. Forecast storm motions between 15-20 knots may also help promote isolated dry lightning strikes over a landscape with ERCs between the 80th to 95th percentiles. ..Moore.. 09/01/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1216 AM CDT Mon Sep 01 2025 Valid 021200Z - 031200Z ...Synopsis... The primary fire weather concern for Tuesday will be the potential for isolated dry thunderstorms across portions of northern CA into portions of northwest NV and central OR. Recent water-vapor imagery depicts a weak upper low off the southern CA coast that is forecast to meander northward over the next 48 hours. As this occurs, lift and mid-level moistening ahead of the wave will promote sufficient destabilization for convection beginning as early as 12z Tuesday morning across central CA, spreading northward through the afternoon and evening. In general, mid-level moisture quality should decrease with northward extent on the fringes of the better monsoonal moisture. An ensemble of forecast soundings suggests PWAT values may range from 0.6 to 0.8 inches across northern CA/northwest NV/central OR, which should favor a mix of wet and dry thunderstorms. Forecast storm motions between 15-20 knots may also help promote isolated dry lightning strikes over a landscape with ERCs between the 80th to 95th percentiles. ..Moore.. 09/01/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1216 AM CDT Mon Sep 01 2025 Valid 021200Z - 031200Z ...Synopsis... The primary fire weather concern for Tuesday will be the potential for isolated dry thunderstorms across portions of northern CA into portions of northwest NV and central OR. Recent water-vapor imagery depicts a weak upper low off the southern CA coast that is forecast to meander northward over the next 48 hours. As this occurs, lift and mid-level moistening ahead of the wave will promote sufficient destabilization for convection beginning as early as 12z Tuesday morning across central CA, spreading northward through the afternoon and evening. In general, mid-level moisture quality should decrease with northward extent on the fringes of the better monsoonal moisture. An ensemble of forecast soundings suggests PWAT values may range from 0.6 to 0.8 inches across northern CA/northwest NV/central OR, which should favor a mix of wet and dry thunderstorms. Forecast storm motions between 15-20 knots may also help promote isolated dry lightning strikes over a landscape with ERCs between the 80th to 95th percentiles. ..Moore.. 09/01/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1216 AM CDT Mon Sep 01 2025 Valid 021200Z - 031200Z ...Synopsis... The primary fire weather concern for Tuesday will be the potential for isolated dry thunderstorms across portions of northern CA into portions of northwest NV and central OR. Recent water-vapor imagery depicts a weak upper low off the southern CA coast that is forecast to meander northward over the next 48 hours. As this occurs, lift and mid-level moistening ahead of the wave will promote sufficient destabilization for convection beginning as early as 12z Tuesday morning across central CA, spreading northward through the afternoon and evening. In general, mid-level moisture quality should decrease with northward extent on the fringes of the better monsoonal moisture. An ensemble of forecast soundings suggests PWAT values may range from 0.6 to 0.8 inches across northern CA/northwest NV/central OR, which should favor a mix of wet and dry thunderstorms. Forecast storm motions between 15-20 knots may also help promote isolated dry lightning strikes over a landscape with ERCs between the 80th to 95th percentiles. ..Moore.. 09/01/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1216 AM CDT Mon Sep 01 2025 Valid 021200Z - 031200Z ...Synopsis... The primary fire weather concern for Tuesday will be the potential for isolated dry thunderstorms across portions of northern CA into portions of northwest NV and central OR. Recent water-vapor imagery depicts a weak upper low off the southern CA coast that is forecast to meander northward over the next 48 hours. As this occurs, lift and mid-level moistening ahead of the wave will promote sufficient destabilization for convection beginning as early as 12z Tuesday morning across central CA, spreading northward through the afternoon and evening. In general, mid-level moisture quality should decrease with northward extent on the fringes of the better monsoonal moisture. An ensemble of forecast soundings suggests PWAT values may range from 0.6 to 0.8 inches across northern CA/northwest NV/central OR, which should favor a mix of wet and dry thunderstorms. Forecast storm motions between 15-20 knots may also help promote isolated dry lightning strikes over a landscape with ERCs between the 80th to 95th percentiles. ..Moore.. 09/01/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

000
ABPZ20 KNHC 010510
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 PM PDT Sun Aug 31 2025

For the eastern and central North Pacific east of 180 longitude:

Active Systems:
The National Hurricane Center is issuing advisories on Tropical
Storm Kiko, located in the east Pacific basin well west-southwest
of the southern tip of the Baja California peninsula. Kiko is
expected to cross into the central Pacific basin late in the week.

South of Southern Mexico:
A tropical wave is producing a large area of disorganized showers
and thunderstorms off the coast of southern Mexico. An area of low
pressure is expected to form from this system within the next day or
two, and it will likely become a tropical depression around the
middle of the week. This system is expected to move
west-northwestward to northwestward at 10 to 15 mph off the coast of
southern and southwestern Mexico during the next few days.
Interests in the Baja California peninsula should monitor the
progress of this disturbance.
* Formation chance through 48 hours...medium...50 percent.
* Formation chance through 7 days...high...80 percent.

&&

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

$$
Forecaster Gibbs

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1150 PM CDT Sun Aug 31 2025 Valid 011200Z - 021200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns are expected to remain limited across the country for today. Localized fire concerns may emerge this afternoon across portions of northeast California and south-central Oregon as southerly winds increase to around 15 mph within a fairly dry and deeply mixed air mass. However, the slow departure of an upper wave over the Pacific Northwest through the day will limit the surface mass response and the potential for strong/sustained gradient winds. Instead, breezy conditions will most likely be driven by diurnal mixing and/or terrain influence, resulting in mainly localized elevated fire weather conditions. ..Moore.. 09/01/2025 ...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 1150 PM CDT Sun Aug 31 2025 Valid 011200Z - 021200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns are expected to remain limited across the country for today. Localized fire concerns may emerge this afternoon across portions of northeast California and south-central Oregon as southerly winds increase to around 15 mph within a fairly dry and deeply mixed air mass. However, the slow departure of an upper wave over the Pacific Northwest through the day will limit the surface mass response and the potential for strong/sustained gradient winds. Instead, breezy conditions will most likely be driven by diurnal mixing and/or terrain influence, resulting in mainly localized elevated fire weather conditions. ..Moore.. 09/01/2025 ...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 1150 PM CDT Sun Aug 31 2025 Valid 011200Z - 021200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns are expected to remain limited across the country for today. Localized fire concerns may emerge this afternoon across portions of northeast California and south-central Oregon as southerly winds increase to around 15 mph within a fairly dry and deeply mixed air mass. However, the slow departure of an upper wave over the Pacific Northwest through the day will limit the surface mass response and the potential for strong/sustained gradient winds. Instead, breezy conditions will most likely be driven by diurnal mixing and/or terrain influence, resulting in mainly localized elevated fire weather conditions. ..Moore.. 09/01/2025 ...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 1150 PM CDT Sun Aug 31 2025 Valid 011200Z - 021200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns are expected to remain limited across the country for today. Localized fire concerns may emerge this afternoon across portions of northeast California and south-central Oregon as southerly winds increase to around 15 mph within a fairly dry and deeply mixed air mass. However, the slow departure of an upper wave over the Pacific Northwest through the day will limit the surface mass response and the potential for strong/sustained gradient winds. Instead, breezy conditions will most likely be driven by diurnal mixing and/or terrain influence, resulting in mainly localized elevated fire weather conditions. ..Moore.. 09/01/2025 ...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 1150 PM CDT Sun Aug 31 2025 Valid 011200Z - 021200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns are expected to remain limited across the country for today. Localized fire concerns may emerge this afternoon across portions of northeast California and south-central Oregon as southerly winds increase to around 15 mph within a fairly dry and deeply mixed air mass. However, the slow departure of an upper wave over the Pacific Northwest through the day will limit the surface mass response and the potential for strong/sustained gradient winds. Instead, breezy conditions will most likely be driven by diurnal mixing and/or terrain influence, resulting in mainly localized elevated fire weather conditions. ..Moore.. 09/01/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more