Aggregator

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0158 AM CDT Sat Sep 28 2024 Valid 291200Z - 301200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE NEBRASKA PANHANDLE AND WESTERN SOUTH DAKOTA... ...Synopsis... A deepening mid to upper-level trough and accompanying jet streak are expected to traverse the western Canadian provinces Sunday. At the surface, a low will deepen across the northern Rockies and tightening pressure gradients will develop from the northern Plains, into the Intermountain West, and Cascades. The result will be increasing surface winds within these areas. A dry return-flow regime over the northern Plains will unfold, where high confidence in the latest guidance suggests speeds around 15-25 mph by the afternoon. Persistent low moisture content of fine to medium fuels across this region, ERCs exceeding 95th percentiles, and RH in the low teens warrants a narrow Critical area from the NE Panhandle through west-central SD. Further west of this region, southwest to westerly winds of slightly lower speeds will impact central WY, southern MT, and portions of ID. Two other Elevated areas have also been included for the Great Basin and Columbia River Basin of WA. Fuels across the former region continue to become more receptive to fire spread due to persistent warm and dry conditions, but only transient elevated to critical south-southwest winds are anticipated. Dry, westerly downslope surface flow near 15 mph coinciding with RH in the upper teens preceding the trough will impact eastern WA. If later guidance suggest a deeper and/or slower trough progression, this Elevated area may need to be expanded. ..Barnes.. 09/28/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1251 AM CDT Sat Sep 28 2024 Valid 291200Z - 301200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms appear unlikely on Sunday. ...Synopsis... An upper-level low in the Tennessee/mid Ohio Valleys will make little progress eastward on Sunday. This low will be weakening and in the process of becoming and open wave during the period. Ridging aloft will be the main feature in the Southwest into the Midwest, while a strong upper-level trough will be present in the Northwest/northern Rockies. At the surface, the pattern will become more disorganized beneath the upper low as that features weakens. A front will remain along and just offshore of the eastern coastline. Thunderstorms are possible from the Florida Peninsula into the Carolinas and southern parts of Virginia. Some modest mid-level flow enhancement will remain in parts of the Southeast and Carolinas. A stronger storm or two could potentially develop in central/eastern North Carolina as heating appears it could support around 1000 J/kg MLCAPE. However, weak lapse rates/warm temperatures aloft will keep buoyancy generally limited and convection rather shallow. The expected environment continues to suggest severe thunderstorm potential is low. A few isolated lightning flashes may also occur in central Utah as a weak upper-level shortwave moves into the Great Basin. Coverage is expected to remain below 10%. ..Wendt.. 09/28/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1251 AM CDT Sat Sep 28 2024 Valid 291200Z - 301200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms appear unlikely on Sunday. ...Synopsis... An upper-level low in the Tennessee/mid Ohio Valleys will make little progress eastward on Sunday. This low will be weakening and in the process of becoming and open wave during the period. Ridging aloft will be the main feature in the Southwest into the Midwest, while a strong upper-level trough will be present in the Northwest/northern Rockies. At the surface, the pattern will become more disorganized beneath the upper low as that features weakens. A front will remain along and just offshore of the eastern coastline. Thunderstorms are possible from the Florida Peninsula into the Carolinas and southern parts of Virginia. Some modest mid-level flow enhancement will remain in parts of the Southeast and Carolinas. A stronger storm or two could potentially develop in central/eastern North Carolina as heating appears it could support around 1000 J/kg MLCAPE. However, weak lapse rates/warm temperatures aloft will keep buoyancy generally limited and convection rather shallow. The expected environment continues to suggest severe thunderstorm potential is low. A few isolated lightning flashes may also occur in central Utah as a weak upper-level shortwave moves into the Great Basin. Coverage is expected to remain below 10%. ..Wendt.. 09/28/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1251 AM CDT Sat Sep 28 2024 Valid 291200Z - 301200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms appear unlikely on Sunday. ...Synopsis... An upper-level low in the Tennessee/mid Ohio Valleys will make little progress eastward on Sunday. This low will be weakening and in the process of becoming and open wave during the period. Ridging aloft will be the main feature in the Southwest into the Midwest, while a strong upper-level trough will be present in the Northwest/northern Rockies. At the surface, the pattern will become more disorganized beneath the upper low as that features weakens. A front will remain along and just offshore of the eastern coastline. Thunderstorms are possible from the Florida Peninsula into the Carolinas and southern parts of Virginia. Some modest mid-level flow enhancement will remain in parts of the Southeast and Carolinas. A stronger storm or two could potentially develop in central/eastern North Carolina as heating appears it could support around 1000 J/kg MLCAPE. However, weak lapse rates/warm temperatures aloft will keep buoyancy generally limited and convection rather shallow. The expected environment continues to suggest severe thunderstorm potential is low. A few isolated lightning flashes may also occur in central Utah as a weak upper-level shortwave moves into the Great Basin. Coverage is expected to remain below 10%. ..Wendt.. 09/28/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1253 AM CDT Sat Sep 28 2024 Valid 281200Z - 291200Z ...Synopsis... Increasing mid-level flow is expected over the Great Basin Saturday between a shortwave trough approaching the CA coast and a ridge centered over the Rockies. Cloud-free skies and heating throughout the day will result in a deeply mixed boundary layer and momentum transfer of this stronger flow to the surface. A few hours of sustained winds reaching 15-20 mph within the Elevated area, along with RH dropping as low as the upper single digits, are expected. In addition, an hour or two of critically sustained winds exceeding 20 mph will be possible within the southern half of the Elevated area, where seasonal ERC values are near the 90th percentile. ..Barnes.. 09/28/2024 ...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 1253 AM CDT Sat Sep 28 2024 Valid 281200Z - 291200Z ...Synopsis... Increasing mid-level flow is expected over the Great Basin Saturday between a shortwave trough approaching the CA coast and a ridge centered over the Rockies. Cloud-free skies and heating throughout the day will result in a deeply mixed boundary layer and momentum transfer of this stronger flow to the surface. A few hours of sustained winds reaching 15-20 mph within the Elevated area, along with RH dropping as low as the upper single digits, are expected. In addition, an hour or two of critically sustained winds exceeding 20 mph will be possible within the southern half of the Elevated area, where seasonal ERC values are near the 90th percentile. ..Barnes.. 09/28/2024 ...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 1253 AM CDT Sat Sep 28 2024 Valid 281200Z - 291200Z ...Synopsis... Increasing mid-level flow is expected over the Great Basin Saturday between a shortwave trough approaching the CA coast and a ridge centered over the Rockies. Cloud-free skies and heating throughout the day will result in a deeply mixed boundary layer and momentum transfer of this stronger flow to the surface. A few hours of sustained winds reaching 15-20 mph within the Elevated area, along with RH dropping as low as the upper single digits, are expected. In addition, an hour or two of critically sustained winds exceeding 20 mph will be possible within the southern half of the Elevated area, where seasonal ERC values are near the 90th percentile. ..Barnes.. 09/28/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1249 AM CDT Sat Sep 28 2024 Valid 281200Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today. General thunderstorms are most likely over the Florida Peninsula during the day. ...Synopsis... An upper low will fill as it moves slowly east across KY, with the overall cyclonic regime extending from the lower Great Lakes to the lower MS Valley. Southwesterly 500 mb winds of 40-60 kt will exist across the Southeast, with an upper ridge from the Four Corners states into the northern Plains. To the west, lowering heights will exist over the Pacific Northwest as a strong shortwave trough pushes into British Columbia, and a weak upper low affects parts of southern CA late. At the surface, weakening low pressure will exist beneath the aforementioned upper low over KY, with only upper 50s to lower 60s F dewpoints stretching across the Appalachians and Piedmont. A weak boundary will exist from the northern Gulf of Mexico across northern FL and along the coastal Carolinas and GA, where 70s F dewpoints will reside. However, very dry midlevel air will exist over the same areas. ...Southeast... Thunderstorm chances look to be maximized over FL today, where vertical profiles will be moist. MUCAPE averaging near 1500 J/kg appears likely over much of the FL Peninsula with the aid of heating. However, lift will be weak and unfocused. Still, the uncapped air mass should yield scattered thunderstorms during the day, possibly beginning early over the eastern Gulf of Mexico and moving ashore. Forecast soundings show weak winds aloft/shear, and generally poor lapse rates with moist profiles. As such, only general thunderstorms are anticipated. ..Jewell/Barnes.. 09/28/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1249 AM CDT Sat Sep 28 2024 Valid 281200Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today. General thunderstorms are most likely over the Florida Peninsula during the day. ...Synopsis... An upper low will fill as it moves slowly east across KY, with the overall cyclonic regime extending from the lower Great Lakes to the lower MS Valley. Southwesterly 500 mb winds of 40-60 kt will exist across the Southeast, with an upper ridge from the Four Corners states into the northern Plains. To the west, lowering heights will exist over the Pacific Northwest as a strong shortwave trough pushes into British Columbia, and a weak upper low affects parts of southern CA late. At the surface, weakening low pressure will exist beneath the aforementioned upper low over KY, with only upper 50s to lower 60s F dewpoints stretching across the Appalachians and Piedmont. A weak boundary will exist from the northern Gulf of Mexico across northern FL and along the coastal Carolinas and GA, where 70s F dewpoints will reside. However, very dry midlevel air will exist over the same areas. ...Southeast... Thunderstorm chances look to be maximized over FL today, where vertical profiles will be moist. MUCAPE averaging near 1500 J/kg appears likely over much of the FL Peninsula with the aid of heating. However, lift will be weak and unfocused. Still, the uncapped air mass should yield scattered thunderstorms during the day, possibly beginning early over the eastern Gulf of Mexico and moving ashore. Forecast soundings show weak winds aloft/shear, and generally poor lapse rates with moist profiles. As such, only general thunderstorms are anticipated. ..Jewell/Barnes.. 09/28/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1249 AM CDT Sat Sep 28 2024 Valid 281200Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today. General thunderstorms are most likely over the Florida Peninsula during the day. ...Synopsis... An upper low will fill as it moves slowly east across KY, with the overall cyclonic regime extending from the lower Great Lakes to the lower MS Valley. Southwesterly 500 mb winds of 40-60 kt will exist across the Southeast, with an upper ridge from the Four Corners states into the northern Plains. To the west, lowering heights will exist over the Pacific Northwest as a strong shortwave trough pushes into British Columbia, and a weak upper low affects parts of southern CA late. At the surface, weakening low pressure will exist beneath the aforementioned upper low over KY, with only upper 50s to lower 60s F dewpoints stretching across the Appalachians and Piedmont. A weak boundary will exist from the northern Gulf of Mexico across northern FL and along the coastal Carolinas and GA, where 70s F dewpoints will reside. However, very dry midlevel air will exist over the same areas. ...Southeast... Thunderstorm chances look to be maximized over FL today, where vertical profiles will be moist. MUCAPE averaging near 1500 J/kg appears likely over much of the FL Peninsula with the aid of heating. However, lift will be weak and unfocused. Still, the uncapped air mass should yield scattered thunderstorms during the day, possibly beginning early over the eastern Gulf of Mexico and moving ashore. Forecast soundings show weak winds aloft/shear, and generally poor lapse rates with moist profiles. As such, only general thunderstorms are anticipated. ..Jewell/Barnes.. 09/28/2024 Read more

811
ABPZ20 KNHC 280513
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 PM PDT Fri Sep 27 2024

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

Offshore of the coast of southwestern Mexico:
An area of low pressure could form early next week off the coast of
southwestern Mexico. Some slow development is possible thereafter
while the system drifts generally westward.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...30 percent.

$$
Forecaster Roberts

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0755 PM CDT Fri Sep 27 2024 Valid 280100Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER EASTERN VIRGINIA...THE DELMARVA...AND FAR EASTERN NORTH CAROLINA... ...SUMMARY... Severe weather potential is forecast to be minimal for the remainder of the period. ...Discussion... The remnants of Helene will remain over the lower OH Valley through tonight, with dry air wrapping around across the Appalachians and into eastern KY/OH. Farther east, drying into eastern VA and vicinity will be more gradual as 850 mb winds veer. In the near term, an area of moisture, instability, and favorable low-level shear will affect much of eastern VA into the DelMarVa and into northeast NC. Storms coverage is expected to remain isolated through the evening, though a brief tornado cannot be ruled out with any small, long-lived storms. Loss of heating as well as drying aloft should preclude any substantial increase in storm coverage. ..Jewell.. 09/28/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0755 PM CDT Fri Sep 27 2024 Valid 280100Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER EASTERN VIRGINIA...THE DELMARVA...AND FAR EASTERN NORTH CAROLINA... ...SUMMARY... Severe weather potential is forecast to be minimal for the remainder of the period. ...Discussion... The remnants of Helene will remain over the lower OH Valley through tonight, with dry air wrapping around across the Appalachians and into eastern KY/OH. Farther east, drying into eastern VA and vicinity will be more gradual as 850 mb winds veer. In the near term, an area of moisture, instability, and favorable low-level shear will affect much of eastern VA into the DelMarVa and into northeast NC. Storms coverage is expected to remain isolated through the evening, though a brief tornado cannot be ruled out with any small, long-lived storms. Loss of heating as well as drying aloft should preclude any substantial increase in storm coverage. ..Jewell.. 09/28/2024 Read more

No Mesoscale Discussions are in effect as of Fri Sep 27 23:30:14 UTC 2024.

Water conservation was urged in New Hampshire since flash drought had developed. WMUR-TV ABC 9 (Manchester, N.H.), Sept 27, 2024

000
ABPZ20 KNHC 272322
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 PM PDT Fri Sep 27 2024

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

Active Systems:
The National Hurricane Center has issued the last advisory on the
remnants of John, located just inland over southwestern Mexico.

Off the coast of southwestern Mexico:
A broad low pressure system could form early next week off the
coast of southwestern Mexico. Some slow development is possible
after that time while the system drifts westward.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...20 percent.

$$
Forecaster Hagen

Nebraska City has a burn ban in effect until there is significant rainfall. The fire chief stated that it is too dry to issue burn permits. News Channel Nebraska (Grand Island), Sept 27, 2024

MD 2127 CONCERNING TORNADO WATCH 688... FOR SOUTHERN/CENTRAL VA INTO EXTREME NORTHERN NC
Mesoscale Discussion 2127 NWS Storm Prediction Center Norman OK 0459 PM CDT Fri Sep 27 2024 Areas affected...Southern/central VA into extreme northern NC Concerning...Tornado Watch 688... Valid 272159Z - 272330Z The severe weather threat for Tornado Watch 688 continues. SUMMARY...Some tornado threat may persist into the evening. Some parts of Tornado Watch 688 have been extended in time to expire at 8 PM EDT. DISCUSSION...At 2155 UTC, two clusters of relatively low-topped convection with embedded rotating cells are ongoing from extreme northern NC into southern/central VA. One cluster is moving northward to the east of Roanoke, near the leading edge of a pronounced midlevel dry slot. The other cluster is moving across the Tidewater region of Virginia, within a persistent low-level warm-advection regime. Extensive cloudiness and poor lapse rates have limited destabilization, but rich low-level moisture is supporting MLCAPE of around 500 J/kg. Notable weakening of low-level flow has been observed from both the KFCX and KAKQ radars, but 0-1 km SRH remains in the 150 m2/s2 range, sufficient to support some tornado threat with any persistent low-topped supercells. Parts of WW 688 have been extended in time to 8 PM EDT in order to address the remaining threat. ..Dean.. 09/27/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...AKQ...LWX...RNK... LAT...LON 36717991 37047998 37678006 37897946 37777828 37727676 37567606 36827603 36417607 36117640 36087704 36697706 36627868 36527935 36567977 36717991 Read more

MD 2126 CONCERNING TORNADO WATCH 688... FOR PARTS OF SOUTHERN VA AND NORTHERN NC
Mesoscale Discussion 2126 NWS Storm Prediction Center Norman OK 0228 PM CDT Fri Sep 27 2024 Areas affected...parts of southern VA and northern NC Concerning...Tornado Watch 688... Valid 271928Z - 272130Z The severe weather threat for Tornado Watch 688 continues. SUMMARY...A brief tornado or two will remain possible for a couple more hours. An additional tornado watch beyond the 22Z expiration of WW 688 appears unlikely. DISCUSSION...Tornado potential has become focused in two regions within WW 688, one near the northeast NC/southeast VA border area and a separate corridor near along the central VA/NC border. The lead convective band has considerably decayed over the past couple hours, but remnants of it continue to move northeast along the northeast NC/southeast VA border area. Surface temperatures and dew points are a couple degrees lower downstream, suggesting the threat will struggle to reintensify. But favorable low-level shear and still adequate tropical boundary-layer moisture suggest a conditional tornado threat remains evident. Farther west, multiple low-topped cells have rotated and produced at least one brief TDS thus far. Surface temperatures have warmed into the low to mid 80s within cloud breaks across central NC and this has compensated for the persistent reduction in low-level SRH per the FCX VWP. A brief tornado or two will remain possible with small discrete cells in this region for another couple hours. ..Grams.. 09/27/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...AKQ...MHX...RAH...RNK... LAT...LON 36937599 36077590 35517682 35627713 36557731 36967770 37097854 36287914 36197962 36448000 37198000 37477964 37487927 37077731 37297671 36937599 Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0338 PM CDT Fri Sep 27 2024 Valid 291200Z - 051200Z Fire weather concerns are expected to emerge late this weekend and into early next week across parts of the northern Rocky Mountains and central to northern Plains. A low-amplitude upper wave is noted in mid-afternoon water-vapor imagery over the eastern Pacific. This wave is expected to amplify slightly as it moves onshore across the Pacific Northwest by early Sunday and translates east into the northern CONUS through Monday. Winds will increase through this period across the northern Rockies and central/northern Plains as an attendant surface low deepens and migrates east in tandem with the upper trough. The combination of strengthening winds, antecedent dry conditions, and receptive fuels should support fire weather concerns. ...D3/Sunday - Northern Rockies and northern Plains... Medium to long-range guidance shows reasonably good agreement in the deepening of a surface low across the northern Rockies and into the southern Canadian Prairies through the day Sunday. Limited moisture return into the region will limit any precipitation chances south of the Canadian border, but the tightening pressure gradient will bolster surface winds across the region. Latest ensemble guidance shows reasonably good agreement in 15-25 mph winds both ahead of and behind the surface trough. Unseasonably warm temperatures will persist through Sunday afternoon, resulting in afternoon RH minimums between 15-25%. With ERCs across much of the region above the 90th percentile (especially across the northern Plains), elevated to critical fire weather conditions appear likely. Critical risk highlights will likely be needed across parts of the northern Plains in subsequent forecast updates as confidence increases that moisture return within the dry return flow regime will be sufficiently limited to allow RH minimums in the teens to low 20s. ...D4/Monday - central Plains... A strong cold front is forecast to push southeast across the northern High Plains and into the Dakotas and NE through the day Monday as the surface cyclone pushes east across the Canadian Prairies. Although cooler temperatures are expected behind the front, diurnal warming should modulate temperature reductions and maintain afternoon highs in the 60s. Coupled with an influx of drier continental air, afternoon RH minimums in the 20-25% range appear probable. A strong wind signal is noted in most solutions suggesting that 20-25 mph post-frontal winds are likely with gusts upwards of 30-40 mph possible. ERCs should remain elevated through Monday afternoon, which will support fire weather concerns. Widespread elevated fire weather conditions are expected, and critical conditions appear probable if current RH forecasts remain on track. ..Moore.. 09/27/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more