SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1058 AM CDT Sat Sep 28 2024 Valid 281630Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today. A relatively quiet convective day is forecast across the CONUS today. Afternoon thunderstorms may affect the higher terrain of northern NM and southern CO, as well as along a weak occluded front from lower MI into NY. Weak instability and limited shear will preclude severe storms. Scattered thunderstorms will also be possible this afternoon and tonight across the FL peninsula and along the GA/SC/NC coast. Weak winds aloft will limit the organization of these storms, with no severe activity expected. ..Hart/Weinman.. 09/28/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1045 AM CDT Sat Sep 28 2024 Valid 281700Z - 291200Z Well above normal to record setting high temperatures are expected in western/southern Arizona today, and east-southeast sustained winds of 10-15 mph gusting to 25 mph with minimum RH of 5-15% will develop across southeast Arizona and far southwest New Mexico. This will lead to locally elevated conditions across southeast Arizona into far southwest New Mexico late this morning and during the afternoon. Otherwise the forecast remains on track and please see the previous forecast for more details. ..Nauslar.. 09/28/2024 .PREV DISCUSSION... /ISSUED 1253 AM CDT Sat Sep 28 2024/ ...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. ...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 1045 AM CDT Sat Sep 28 2024 Valid 281700Z - 291200Z Well above normal to record setting high temperatures are expected in western/southern Arizona today, and east-southeast sustained winds of 10-15 mph gusting to 25 mph with minimum RH of 5-15% will develop across southeast Arizona and far southwest New Mexico. This will lead to locally elevated conditions across southeast Arizona into far southwest New Mexico late this morning and during the afternoon. Otherwise the forecast remains on track and please see the previous forecast for more details. ..Nauslar.. 09/28/2024 .PREV DISCUSSION... /ISSUED 1253 AM CDT Sat Sep 28 2024/ ...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. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0738 AM CDT Sat Sep 28 2024 Valid 281300Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today. ...Synopsis/Discussion... The mid/upper-level pattern features mean ridging over the West and troughing in the East. The pattern is anchored by a large, nearly stacked cyclone -- resulting from the combination of an antecedent midlatitude low with the post-tropical remnants of Helene. The cyclone should remain centered over the lower Ohio Valley region, drifting/wobbling erratically eastward over northern KY through the period, while continuing to fill. The strongest associated mid/ upper-level winds should remain mostly behind a low-level frontal zone extending from the northern Gulf across northern FL to the coastal Carolinas. South of the boundary across parts of peninsular FL, sufficient low-level moisture remains -- amid weak to negligible MLCINH and a deep troposphere with modest but sufficient lapse rates for convection. This will support scattered thunderstorms today over FL, with isolated thunderstorm potential over coastal areas of GA/Carolinas near the boundary. Dry midlevel air and lack of greater flow/shear should keep severe potential too isolated and disorganized for an outlook. Elsewhere, just east of the mean ridge and amid northerly flow very peripheral to the cyclone, a patch of marginally favorable low/ middle-level moisture should combine with diurnal heating of higher terrain over parts of northern NM and southern CO. Scattered showers are expected this afternoon, with isolated to widely scattered convection extending above a mid/upper-level stable layer and into icing regions suitable for lightning generation. Isolated thunderstorms also are possible amid weak but sufficient low-level moisture and instability around parts of the eastern Great Lakes. ..Edwards/Broyles.. 09/28/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0738 AM CDT Sat Sep 28 2024 Valid 281300Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today. ...Synopsis/Discussion... The mid/upper-level pattern features mean ridging over the West and troughing in the East. The pattern is anchored by a large, nearly stacked cyclone -- resulting from the combination of an antecedent midlatitude low with the post-tropical remnants of Helene. The cyclone should remain centered over the lower Ohio Valley region, drifting/wobbling erratically eastward over northern KY through the period, while continuing to fill. The strongest associated mid/ upper-level winds should remain mostly behind a low-level frontal zone extending from the northern Gulf across northern FL to the coastal Carolinas. South of the boundary across parts of peninsular FL, sufficient low-level moisture remains -- amid weak to negligible MLCINH and a deep troposphere with modest but sufficient lapse rates for convection. This will support scattered thunderstorms today over FL, with isolated thunderstorm potential over coastal areas of GA/Carolinas near the boundary. Dry midlevel air and lack of greater flow/shear should keep severe potential too isolated and disorganized for an outlook. Elsewhere, just east of the mean ridge and amid northerly flow very peripheral to the cyclone, a patch of marginally favorable low/ middle-level moisture should combine with diurnal heating of higher terrain over parts of northern NM and southern CO. Scattered showers are expected this afternoon, with isolated to widely scattered convection extending above a mid/upper-level stable layer and into icing regions suitable for lightning generation. Isolated thunderstorms also are possible amid weak but sufficient low-level moisture and instability around parts of the eastern Great Lakes. ..Edwards/Broyles.. 09/28/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0322 AM CDT Sat Sep 28 2024 Valid 011200Z - 061200Z ...DISCUSSION... By the middle of next week, upper-level flow across the CONUS is expected to become more zonal and the jet stream will be generally located along the Canadian border. The more pronounced troughs in the northern CONUS will help to push cooler drier air into much of the country. A modestly moist airmass will be limited to portions of the Southeast. Broadly stable conditions will limit severe thunderstorm potential at least through the end of the week. Model guidance shows some potential for flow aloft to amplify next weekend. This could encourage moisture return northward. However, the quality of this moisture as well as the timing of upper-level troughs is highly uncertain this far in advance. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0322 AM CDT Sat Sep 28 2024 Valid 011200Z - 061200Z ...DISCUSSION... By the middle of next week, upper-level flow across the CONUS is expected to become more zonal and the jet stream will be generally located along the Canadian border. The more pronounced troughs in the northern CONUS will help to push cooler drier air into much of the country. A modestly moist airmass will be limited to portions of the Southeast. Broadly stable conditions will limit severe thunderstorm potential at least through the end of the week. Model guidance shows some potential for flow aloft to amplify next weekend. This could encourage moisture return northward. However, the quality of this moisture as well as the timing of upper-level troughs is highly uncertain this far in advance. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0204 AM CDT Sat Sep 28 2024 Valid 301200Z - 011200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not likely on Monday. ...Synopsis... A positively tilted and weakening upper trough will continue to linger in parts of the Mid-Atlantic and Southeast on Monday. Similar to previous days, a belt of stronger mid-level winds will still be present from eastern Georgia into the eastern Carolinas. The surface pattern in the East will remain quite diffuse. A stronger upper-level trough will move eastward into the upper Great Lakes region. A relatively sharp cold front will be attendant to this upper-level system and bring cooler and much drier conditions into much of the Plains. A few thunderstorms are possible in association with the weakening trough in eastern parts of the Carolinas. Weak lapse rates aloft and overall nebulous forcing will continue to limit severe potential with any storms that do develop. Farther west, thunderstorms are much less likely as warm air at mid/upper levels will keep convection too shallow for charge separation. Heating of a moist airmass and lift from the sea breeze boundaries will promote thunderstorms in the Florida Peninsula. Much weaker flow aloft will greatly limit storm organization, however. ..Wendt.. 09/28/2024 Read more

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 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 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

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

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

WW 0688 Status Updates
STATUS REPORT ON WW 688 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 ESE ECG TO 45 SE RZZ TO 25 SSE RIC TO 40 E RIC TO 35 SW NHK TO 40 NW AVC TO 10 SSE DAN TO 10 WNW DAN. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 2126. ..GRAMS..09/27/24 ATTN...WFO...RAH...MHX...AKQ...ILM...GSP...RNK...CAE... STATUS REPORT FOR WT 688 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS NCC015-029-041-053-073-091-139-143-272140- NC . NORTH CAROLINA COUNTIES INCLUDED ARE BERTIE CAMDEN CHOWAN CURRITUCK GATES HERTFORD PASQUOTANK PERQUIMANS VAC009-011-019-029-031-037-067-083-093-095-143-175-181-183-199- 550-590-620-650-680-700-710-735-740-800-810-830-272140- VA . VIRGINIA COUNTIES INCLUDED ARE AMHERST APPOMATTOX BEDFORD BUCKINGHAM CAMPBELL CHARLOTTE FRANKLIN HALIFAX ISLE OF WIGHT JAMES CITY PITTSYLVANIA SOUTHAMPTON SURRY SUSSEX YORK Read more