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SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0620 PM CST Tue Jan 16 2024 Valid 170100Z - 171200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected tonight. ...South FL... Diminishing thunderstorm coverage is anticipated across the south Peninsula and Keys amid weak tropospheric lapse rates of 5-6 C/km and MLCAPE around 500-750 J/kg per 00Z MFL/KEY RAOBs. As a trailing cold front makes steady southeast progression, the bulk of thunderstorm activity has become confined off both coasts. With decreasing low-level convergence along the front over land, this trend is anticipated to continue. As such, thunderstorm probabilities will likely become negligible overnight. ..Grams.. 01/17/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0620 PM CST Tue Jan 16 2024 Valid 170100Z - 171200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected tonight. ...South FL... Diminishing thunderstorm coverage is anticipated across the south Peninsula and Keys amid weak tropospheric lapse rates of 5-6 C/km and MLCAPE around 500-750 J/kg per 00Z MFL/KEY RAOBs. As a trailing cold front makes steady southeast progression, the bulk of thunderstorm activity has become confined off both coasts. With decreasing low-level convergence along the front over land, this trend is anticipated to continue. As such, thunderstorm probabilities will likely become negligible overnight. ..Grams.. 01/17/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0620 PM CST Tue Jan 16 2024 Valid 170100Z - 171200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected tonight. ...South FL... Diminishing thunderstorm coverage is anticipated across the south Peninsula and Keys amid weak tropospheric lapse rates of 5-6 C/km and MLCAPE around 500-750 J/kg per 00Z MFL/KEY RAOBs. As a trailing cold front makes steady southeast progression, the bulk of thunderstorm activity has become confined off both coasts. With decreasing low-level convergence along the front over land, this trend is anticipated to continue. As such, thunderstorm probabilities will likely become negligible overnight. ..Grams.. 01/17/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0620 PM CST Tue Jan 16 2024 Valid 170100Z - 171200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected tonight. ...South FL... Diminishing thunderstorm coverage is anticipated across the south Peninsula and Keys amid weak tropospheric lapse rates of 5-6 C/km and MLCAPE around 500-750 J/kg per 00Z MFL/KEY RAOBs. As a trailing cold front makes steady southeast progression, the bulk of thunderstorm activity has become confined off both coasts. With decreasing low-level convergence along the front over land, this trend is anticipated to continue. As such, thunderstorm probabilities will likely become negligible overnight. ..Grams.. 01/17/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0620 PM CST Tue Jan 16 2024 Valid 170100Z - 171200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected tonight. ...South FL... Diminishing thunderstorm coverage is anticipated across the south Peninsula and Keys amid weak tropospheric lapse rates of 5-6 C/km and MLCAPE around 500-750 J/kg per 00Z MFL/KEY RAOBs. As a trailing cold front makes steady southeast progression, the bulk of thunderstorm activity has become confined off both coasts. With decreasing low-level convergence along the front over land, this trend is anticipated to continue. As such, thunderstorm probabilities will likely become negligible overnight. ..Grams.. 01/17/2024 Read more

No watches are valid as of Tue Jan 16 23:33:02 UTC 2024.

MD 0076 CONCERNING FREEZING RAIN FOR PORTIONS OF NORTHWEST OR INTO FAR SOUTHWEST WA
Mesoscale Discussion 0076 NWS Storm Prediction Center Norman OK 0531 PM CST Tue Jan 16 2024 Areas affected...Portions of northwest OR into far southwest WA Concerning...Freezing rain Valid 162331Z - 170400Z SUMMARY...Freezing rain will increase in both intensity and coverage across much of the Willamette Valley, the Oregon Coast Range, and the far southern Chehalis River Valley during the next 1-2 hours and persist through around 04Z. DISCUSSION...Latest water vapor imagery depicts a compact midlevel cyclone tracking eastward toward the Pacific Northwest. Strong DCVA preceding the cyclone should overspread coastal OR over the next 1-2 hours, supporting an increase in precipitation intensity and coverage across the region. The 12Z SLE observed sounding and more recent Portland ACARS soundings showed lingering dry air in the 1-5-km layer, though persistent precipitation (and related wet-bulbing) along with increasing moisture ahead of the aforementioned cyclone are likely contributing to a deep saturated layer which will further support increasing precipitation rates. In fact, freezing rain is beginning to increase in coverage across coastal OR per the latest surface observations. Low to mid 20s surface wet bulb temperatures beneath a 3-4 deg C warm nose as low as 925 mb in the Willamette Valley into the Oregon Coast Range will support complete hydrometeor melting and re-freezing at the surface, suggesting that freezing rain will be the predominant precipitation type (with pockets of sleet also possible). And, given the strengthening large-scale ascent amid a deeply saturated thermodynamic profile, freezing rain rates could exceed 0.1 inch/hour. These conditions will likely persist through around 04Z, before surface temperatures begin to warm and the dry conveyor belt accompanying the midlevel cyclone impinges on the area. ..Weinman.. 01/16/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MFR...SEW...PQR... LAT...LON 44262371 44892370 44992384 45192392 45342363 45682358 46122370 46472335 46522282 45892250 45412222 45042253 44372277 44022285 43742309 43792355 44262371 Read more

No Mesoscale Discussions are in effect as of Tue Jan 16 22:46:02 UTC 2024.

MD 0075 CONCERNING HEAVY SNOW FOR MUCH OF INTERIOR MAINE
Mesoscale Discussion 0075 NWS Storm Prediction Center Norman OK 1249 PM CST Tue Jan 16 2024 Areas affected...Much of interior Maine Concerning...Heavy snow Valid 161849Z - 162245Z SUMMARY...Heavy snow rates on the order of 1-2 inches per hour are increasingly likely by 4-7 PM EST, and probably will linger further into the evening, before spreading to the northeast of the region. DISCUSSION...Downstream of a significant short wave impulse turning northeastward through the lower Great Lakes region, cyclogenesis is underway along a surface frontal zone near the northern Mid Atlantic through southern New England coast vicinity. Associated large-scale ascent is contributing to an expanding and intensifying precipitation shield beneath cooling cloud tops inland of coastal areas. It appears that this will continue while overspreading the remainder of northern New England through the balance of the afternoon, in response to further strengthening of lower/mid-tropospheric warm advection and forcing for upward vertical motion. A general consensus of latest model output indicates a more rapid deepening of the surface cyclone will commence by 21-00Z, largely offshore, across and northeast of the Cape Cod vicinity by 21-00Z. Across the coastal plain into higher terrain of Maine, deep-layer lift, becoming maximized within the mid-level layer favorably cold for large dendritic ice crystal growth, is forecast to become increasingly conducive to heavy snow rates around or above 1 inch per hour by 21-22Z, if not earlier. This will be aided by cold thermodynamic profiles entirely below freezing, and supportive of moderately large snow to liquid water equivalent ratios, as low-level moisture advection off the Atlantic contributes to increasing precipitable water content (.4 to .6 inches). Strengthening frontogentic forcing may contribute to bands of heavier snow rates approaching 2 inches per hour, with the heavy snow lingering through mid to late evening before diminishing and/or spreading with the large-scale ascent northeast of the region. ..Kerr.. 01/16/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...CAR...GYX... LAT...LON 45666715 44236966 43657102 44227114 45277053 46276909 46776794 45666715 Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0257 PM CST Tue Jan 16 2024 Valid 181200Z - 241200Z A progressive upper-level pattern is expected across the CONUS for the extended forecast period. A mid-level trough will eject into the Atlantic late this week as an upper-ridge builds over the Great Plains this weekend. Thereafter, another upper trough is poised to overspread the central U.S. by early next week. Surface high pressure and associated cold air will meander over the central and eastern U.S. through at least this weekend. With the passing of the upper ridge, relatively warmer, but moister low-level air will return northward from the Gulf of Mexico and overspread the south-central CONUS. The net result will be cool and/or moist surface conditions that will limit wildfire-spread potential over most of the CONUS. ..Squitieri.. 01/16/2024 ...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 0257 PM CST Tue Jan 16 2024 Valid 181200Z - 241200Z A progressive upper-level pattern is expected across the CONUS for the extended forecast period. A mid-level trough will eject into the Atlantic late this week as an upper-ridge builds over the Great Plains this weekend. Thereafter, another upper trough is poised to overspread the central U.S. by early next week. Surface high pressure and associated cold air will meander over the central and eastern U.S. through at least this weekend. With the passing of the upper ridge, relatively warmer, but moister low-level air will return northward from the Gulf of Mexico and overspread the south-central CONUS. The net result will be cool and/or moist surface conditions that will limit wildfire-spread potential over most of the CONUS. ..Squitieri.. 01/16/2024 ...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 0257 PM CST Tue Jan 16 2024 Valid 181200Z - 241200Z A progressive upper-level pattern is expected across the CONUS for the extended forecast period. A mid-level trough will eject into the Atlantic late this week as an upper-ridge builds over the Great Plains this weekend. Thereafter, another upper trough is poised to overspread the central U.S. by early next week. Surface high pressure and associated cold air will meander over the central and eastern U.S. through at least this weekend. With the passing of the upper ridge, relatively warmer, but moister low-level air will return northward from the Gulf of Mexico and overspread the south-central CONUS. The net result will be cool and/or moist surface conditions that will limit wildfire-spread potential over most of the CONUS. ..Squitieri.. 01/16/2024 ...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 0257 PM CST Tue Jan 16 2024 Valid 181200Z - 241200Z A progressive upper-level pattern is expected across the CONUS for the extended forecast period. A mid-level trough will eject into the Atlantic late this week as an upper-ridge builds over the Great Plains this weekend. Thereafter, another upper trough is poised to overspread the central U.S. by early next week. Surface high pressure and associated cold air will meander over the central and eastern U.S. through at least this weekend. With the passing of the upper ridge, relatively warmer, but moister low-level air will return northward from the Gulf of Mexico and overspread the south-central CONUS. The net result will be cool and/or moist surface conditions that will limit wildfire-spread potential over most of the CONUS. ..Squitieri.. 01/16/2024 ...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 0257 PM CST Tue Jan 16 2024 Valid 181200Z - 241200Z A progressive upper-level pattern is expected across the CONUS for the extended forecast period. A mid-level trough will eject into the Atlantic late this week as an upper-ridge builds over the Great Plains this weekend. Thereafter, another upper trough is poised to overspread the central U.S. by early next week. Surface high pressure and associated cold air will meander over the central and eastern U.S. through at least this weekend. With the passing of the upper ridge, relatively warmer, but moister low-level air will return northward from the Gulf of Mexico and overspread the south-central CONUS. The net result will be cool and/or moist surface conditions that will limit wildfire-spread potential over most of the CONUS. ..Squitieri.. 01/16/2024 ...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 0257 PM CST Tue Jan 16 2024 Valid 181200Z - 241200Z A progressive upper-level pattern is expected across the CONUS for the extended forecast period. A mid-level trough will eject into the Atlantic late this week as an upper-ridge builds over the Great Plains this weekend. Thereafter, another upper trough is poised to overspread the central U.S. by early next week. Surface high pressure and associated cold air will meander over the central and eastern U.S. through at least this weekend. With the passing of the upper ridge, relatively warmer, but moister low-level air will return northward from the Gulf of Mexico and overspread the south-central CONUS. The net result will be cool and/or moist surface conditions that will limit wildfire-spread potential over most of the CONUS. ..Squitieri.. 01/16/2024 ...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 0257 PM CST Tue Jan 16 2024 Valid 181200Z - 241200Z A progressive upper-level pattern is expected across the CONUS for the extended forecast period. A mid-level trough will eject into the Atlantic late this week as an upper-ridge builds over the Great Plains this weekend. Thereafter, another upper trough is poised to overspread the central U.S. by early next week. Surface high pressure and associated cold air will meander over the central and eastern U.S. through at least this weekend. With the passing of the upper ridge, relatively warmer, but moister low-level air will return northward from the Gulf of Mexico and overspread the south-central CONUS. The net result will be cool and/or moist surface conditions that will limit wildfire-spread potential over most of the CONUS. ..Squitieri.. 01/16/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0148 PM CST Tue Jan 16 2024 Valid 162000Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE FLORIDA PENINSULA... ...SUMMARY... A brief tornado or two and isolated damaging winds are possible through this afternoon across central Florida. ...Florida... Scattered storms continue to develop ahead of a front and within the moist air mass, although heating has become quite limited. Convergence is relatively weak along the boundary, which has become relatively stationary, but the uncapped air mass to the south along with favorable time of day should continue to support scattered development with MLCAPE to 1500 J/kg. Deep-layer shear is favorable for fast-moving and sustained storms with 50-60 kt, and winds do veer with height especially over the eastern part of the Peninsula. As such, a storm or two could become a supercell this afternoon with the risk of a tornado, but overall coverage of severe storms should remain isolated given minimal large-scale support and gradually veering low-level winds. ..Jewell.. 01/16/2024 .PREV DISCUSSION... /ISSUED 1001 AM CST Tue Jan 16 2024/ ...Central FL this afternoon... A broad midlevel trough from the Ozarks to the OH Valley will progress eastward to the Atlantic coast by late tonight, as an associated surface cold front moves southeastward across central/south FL. A subtle/embedded speed max over the northern Gulf of Mexico will move over north FL this afternoon, and this will help focus thunderstorm development through the day across central FL, both along and south of the cold front. Midlevel lapse rates will not be steep, but some cloud breaks north of ongoing convection and boundary-layer dewpoints in the low 70s will contribute to MLCAPE near 1000 J/kg ahead of the cold front, and somewhat larger buoyancy along the southern fringes of the ongoing convection in central FL. The storms west of Tampa have shown some increase in intensity along the front, and additional storm development is possible along the southern periphery of the ongoing storms across central FL. Deep-layer vertical shear/hodograph length will be sufficient for some organized/rotating storms, while low-level hodograph curvature/SRH will remain relatively larger through early afternoon and begin to decrease by mid-late afternoon as low-level flow veers. The net result will be the potential for line segments or supercells capable of producing isolated wind damage. A brief tornado or two will also be possible, focused a little more toward the Atlantic coast where low-level shear will be modestly stronger through more of the afternoon. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0148 PM CST Tue Jan 16 2024 Valid 162000Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE FLORIDA PENINSULA... ...SUMMARY... A brief tornado or two and isolated damaging winds are possible through this afternoon across central Florida. ...Florida... Scattered storms continue to develop ahead of a front and within the moist air mass, although heating has become quite limited. Convergence is relatively weak along the boundary, which has become relatively stationary, but the uncapped air mass to the south along with favorable time of day should continue to support scattered development with MLCAPE to 1500 J/kg. Deep-layer shear is favorable for fast-moving and sustained storms with 50-60 kt, and winds do veer with height especially over the eastern part of the Peninsula. As such, a storm or two could become a supercell this afternoon with the risk of a tornado, but overall coverage of severe storms should remain isolated given minimal large-scale support and gradually veering low-level winds. ..Jewell.. 01/16/2024 .PREV DISCUSSION... /ISSUED 1001 AM CST Tue Jan 16 2024/ ...Central FL this afternoon... A broad midlevel trough from the Ozarks to the OH Valley will progress eastward to the Atlantic coast by late tonight, as an associated surface cold front moves southeastward across central/south FL. A subtle/embedded speed max over the northern Gulf of Mexico will move over north FL this afternoon, and this will help focus thunderstorm development through the day across central FL, both along and south of the cold front. Midlevel lapse rates will not be steep, but some cloud breaks north of ongoing convection and boundary-layer dewpoints in the low 70s will contribute to MLCAPE near 1000 J/kg ahead of the cold front, and somewhat larger buoyancy along the southern fringes of the ongoing convection in central FL. The storms west of Tampa have shown some increase in intensity along the front, and additional storm development is possible along the southern periphery of the ongoing storms across central FL. Deep-layer vertical shear/hodograph length will be sufficient for some organized/rotating storms, while low-level hodograph curvature/SRH will remain relatively larger through early afternoon and begin to decrease by mid-late afternoon as low-level flow veers. The net result will be the potential for line segments or supercells capable of producing isolated wind damage. A brief tornado or two will also be possible, focused a little more toward the Atlantic coast where low-level shear will be modestly stronger through more of the afternoon. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0148 PM CST Tue Jan 16 2024 Valid 162000Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE FLORIDA PENINSULA... ...SUMMARY... A brief tornado or two and isolated damaging winds are possible through this afternoon across central Florida. ...Florida... Scattered storms continue to develop ahead of a front and within the moist air mass, although heating has become quite limited. Convergence is relatively weak along the boundary, which has become relatively stationary, but the uncapped air mass to the south along with favorable time of day should continue to support scattered development with MLCAPE to 1500 J/kg. Deep-layer shear is favorable for fast-moving and sustained storms with 50-60 kt, and winds do veer with height especially over the eastern part of the Peninsula. As such, a storm or two could become a supercell this afternoon with the risk of a tornado, but overall coverage of severe storms should remain isolated given minimal large-scale support and gradually veering low-level winds. ..Jewell.. 01/16/2024 .PREV DISCUSSION... /ISSUED 1001 AM CST Tue Jan 16 2024/ ...Central FL this afternoon... A broad midlevel trough from the Ozarks to the OH Valley will progress eastward to the Atlantic coast by late tonight, as an associated surface cold front moves southeastward across central/south FL. A subtle/embedded speed max over the northern Gulf of Mexico will move over north FL this afternoon, and this will help focus thunderstorm development through the day across central FL, both along and south of the cold front. Midlevel lapse rates will not be steep, but some cloud breaks north of ongoing convection and boundary-layer dewpoints in the low 70s will contribute to MLCAPE near 1000 J/kg ahead of the cold front, and somewhat larger buoyancy along the southern fringes of the ongoing convection in central FL. The storms west of Tampa have shown some increase in intensity along the front, and additional storm development is possible along the southern periphery of the ongoing storms across central FL. Deep-layer vertical shear/hodograph length will be sufficient for some organized/rotating storms, while low-level hodograph curvature/SRH will remain relatively larger through early afternoon and begin to decrease by mid-late afternoon as low-level flow veers. The net result will be the potential for line segments or supercells capable of producing isolated wind damage. A brief tornado or two will also be possible, focused a little more toward the Atlantic coast where low-level shear will be modestly stronger through more of the afternoon. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0148 PM CST Tue Jan 16 2024 Valid 162000Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE FLORIDA PENINSULA... ...SUMMARY... A brief tornado or two and isolated damaging winds are possible through this afternoon across central Florida. ...Florida... Scattered storms continue to develop ahead of a front and within the moist air mass, although heating has become quite limited. Convergence is relatively weak along the boundary, which has become relatively stationary, but the uncapped air mass to the south along with favorable time of day should continue to support scattered development with MLCAPE to 1500 J/kg. Deep-layer shear is favorable for fast-moving and sustained storms with 50-60 kt, and winds do veer with height especially over the eastern part of the Peninsula. As such, a storm or two could become a supercell this afternoon with the risk of a tornado, but overall coverage of severe storms should remain isolated given minimal large-scale support and gradually veering low-level winds. ..Jewell.. 01/16/2024 .PREV DISCUSSION... /ISSUED 1001 AM CST Tue Jan 16 2024/ ...Central FL this afternoon... A broad midlevel trough from the Ozarks to the OH Valley will progress eastward to the Atlantic coast by late tonight, as an associated surface cold front moves southeastward across central/south FL. A subtle/embedded speed max over the northern Gulf of Mexico will move over north FL this afternoon, and this will help focus thunderstorm development through the day across central FL, both along and south of the cold front. Midlevel lapse rates will not be steep, but some cloud breaks north of ongoing convection and boundary-layer dewpoints in the low 70s will contribute to MLCAPE near 1000 J/kg ahead of the cold front, and somewhat larger buoyancy along the southern fringes of the ongoing convection in central FL. The storms west of Tampa have shown some increase in intensity along the front, and additional storm development is possible along the southern periphery of the ongoing storms across central FL. Deep-layer vertical shear/hodograph length will be sufficient for some organized/rotating storms, while low-level hodograph curvature/SRH will remain relatively larger through early afternoon and begin to decrease by mid-late afternoon as low-level flow veers. The net result will be the potential for line segments or supercells capable of producing isolated wind damage. A brief tornado or two will also be possible, focused a little more toward the Atlantic coast where low-level shear will be modestly stronger through more of the afternoon. Read more