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SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1123 PM CST Fri Jan 12 2024 Valid 131200Z - 141200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorm threat is negligible today. ...Discussion... Intense 12hr midlevel height falls will spread across New England over the next 30 hr in response to an upper trough that is expected to advance across the Great Lakes toward Georgian Bay by the end of the period. Strong low-level warm advection early in the period will likely contribute to ascent necessary for elevated convection. Forecast soundings suggest parcels lifted near 850mb will yield MUCAPE on the order of 500 J/kg, more than adequate for lightning discharge in the more robust updrafts. Farther south, weak buoyancy lingers across south FL. Weak low-level convergence along the front may prove adequate for instigating surface-based updrafts capable of generating lightning. Primary threat should be prior to 21z. ..Darrow/Weinman.. 01/13/2024 Read more

MD 0058 CONCERNING HEAVY SNOW FOR PORTIONS OF NORTHERN/CENTRAL LOWER MICHIGAN AND FAR NORTHEAST WISCONSIN
Mesoscale Discussion 0058 NWS Storm Prediction Center Norman OK 0547 PM CST Fri Jan 12 2024 Areas affected...Portions of northern/central Lower Michigan and far northeast Wisconsin Concerning...Heavy snow Valid 122347Z - 130345Z SUMMARY...Heavy snow with rates of 1 to locally 2 in/hr will continue spreading northward across Lower MI and northeast WI this evening. DISCUSSION...A fairly expansive swath of heavy snow with rates near 1 in/hr are ongoing across much of Lower MI this evening, largely driven by a deep band of isentropic ascent ahead of a 984 mb surface cyclone currently over northeast IL. Latest web cams across Lower MI show snow sticking to roadways as surface temperatures continue to nocturnally cool. Over the next few hours, the strong isentropic ascent (50-60-kt 1-2 km cross-isotherm flow per regional VWP) will continue northward in tandem with the northeastward-moving surface cyclone. This will occur as ascent in the left exit region of a robust southwesterly jet streak overspreads the area. The strengthening deep-layer ascent coupled with increasingly cold thermodynamic profiles with northward extent will continue to support heavy snow with rates of 1-2 in/hr given a deep/saturated dendritic growth zone. The best chance for localized 2 in/hr rates could develop across northeastern Lower MI from 00-04Z, where colder temperatures and stronger ascent should overlap for a couple hours (supported by the latest high-resolution guidance). In addition, a modest pressure gradient and related breezy surface winds should continue to favor visibility reductions to 0.25 miles in the heavier bursts of snow. ..Weinman.. 01/12/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DTX...APX...GRR...MQT...GRB...MKX... LAT...LON 42828544 43098686 43428775 43928809 44788799 45568719 45918639 45978545 45868442 45598376 45088307 44198258 43668248 43008299 42778397 42828544 Read more

MD 0059 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR EASTERN GEORGIA...EASTERN SOUTH CAROLINA AND EASTERN NORTH CAROLINA
Mesoscale Discussion 0059 NWS Storm Prediction Center Norman OK 0627 PM CST Fri Jan 12 2024 Areas affected...Eastern Georgia...Eastern South Carolina and eastern North Carolina Concerning...Severe potential...Watch unlikely Valid 130027Z - 130300Z Probability of Watch Issuance...20 percent SUMMARY...A marginal severe threat may develop across parts of far eastern Georgia, eastern South Carolina and eastern North Carolina over the next 1 to 2 hours. No weather watch issuance is expected. DISCUSSION...The latest radar imagery shows a band of convection oriented from south-southwest to north-northeast from southern Georgia to central North Carolina. This convection is located along the northern edge of a weakly unstable airmass, where the RAP is analyzing MLCAPE below 500 J/kg. In spite of the weak instability, moisture advection will occur across the eastern Carolinas over the next couple of hours, which will result in a gradually increase in instability. In addition, regional WSR-88D VWPs in the eastern Carolinas have very strong deep-layer shear, associated with the eastern edge of a broad mid-level jet. For this reason, there will be potential for weakly organized rotating storms. Although a weak tornado or strong wind gust will be possible, the threat should remain isolated as the upper-level system over the Northeast pulls away from the region. ..Broyles/Goss.. 01/13/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...AKQ...MHX...RAH...ILM...CHS...CAE... LAT...LON 32987960 33807852 34557718 35057642 35467626 35817655 35927717 35697769 34877907 33278130 32628187 32228190 31918151 32028085 32987960 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0639 PM CST Fri Jan 12 2024 Valid 130100Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHEASTERN US... ...SUMMARY... Isolated damaging winds and perhaps a tornado remain possible tonight across portions of the southeastern US. ...01z Update... Primary upper low is shifting northeast toward southern WI early this evening as main midlevel jet translates across the TN Valley. With the upper system now focused over the Great Lakes, trailing cold front is less dynamically focused but should still remain the primary mechanism for convective development this evening. 00z soundings ahead of the front exhibit around 6.5-7C/km midlevel lapse rates at JAX/CHS, but notably weaker over the FL Peninsula where surface-based parcels are less inhibited. Latest radar data suggests the strongest updrafts should continue along the southern influence of the upper trough where surface-based buoyancy supports robust updrafts -- namely southern GA northern FL. Even so, most of this activity has not produced severe wind/hail and any supercell structures are notably weak. Even so, strong shear will continue to support the potential for robust updrafts, though boundary-layer recovery may struggle to reach levels necessary for widespread, organized updrafts. ..Darrow.. 01/13/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0639 PM CST Fri Jan 12 2024 Valid 130100Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHEASTERN US... ...SUMMARY... Isolated damaging winds and perhaps a tornado remain possible tonight across portions of the southeastern US. ...01z Update... Primary upper low is shifting northeast toward southern WI early this evening as main midlevel jet translates across the TN Valley. With the upper system now focused over the Great Lakes, trailing cold front is less dynamically focused but should still remain the primary mechanism for convective development this evening. 00z soundings ahead of the front exhibit around 6.5-7C/km midlevel lapse rates at JAX/CHS, but notably weaker over the FL Peninsula where surface-based parcels are less inhibited. Latest radar data suggests the strongest updrafts should continue along the southern influence of the upper trough where surface-based buoyancy supports robust updrafts -- namely southern GA northern FL. Even so, most of this activity has not produced severe wind/hail and any supercell structures are notably weak. Even so, strong shear will continue to support the potential for robust updrafts, though boundary-layer recovery may struggle to reach levels necessary for widespread, organized updrafts. ..Darrow.. 01/13/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0639 PM CST Fri Jan 12 2024 Valid 130100Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHEASTERN US... ...SUMMARY... Isolated damaging winds and perhaps a tornado remain possible tonight across portions of the southeastern US. ...01z Update... Primary upper low is shifting northeast toward southern WI early this evening as main midlevel jet translates across the TN Valley. With the upper system now focused over the Great Lakes, trailing cold front is less dynamically focused but should still remain the primary mechanism for convective development this evening. 00z soundings ahead of the front exhibit around 6.5-7C/km midlevel lapse rates at JAX/CHS, but notably weaker over the FL Peninsula where surface-based parcels are less inhibited. Latest radar data suggests the strongest updrafts should continue along the southern influence of the upper trough where surface-based buoyancy supports robust updrafts -- namely southern GA northern FL. Even so, most of this activity has not produced severe wind/hail and any supercell structures are notably weak. Even so, strong shear will continue to support the potential for robust updrafts, though boundary-layer recovery may struggle to reach levels necessary for widespread, organized updrafts. ..Darrow.. 01/13/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0639 PM CST Fri Jan 12 2024 Valid 130100Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHEASTERN US... ...SUMMARY... Isolated damaging winds and perhaps a tornado remain possible tonight across portions of the southeastern US. ...01z Update... Primary upper low is shifting northeast toward southern WI early this evening as main midlevel jet translates across the TN Valley. With the upper system now focused over the Great Lakes, trailing cold front is less dynamically focused but should still remain the primary mechanism for convective development this evening. 00z soundings ahead of the front exhibit around 6.5-7C/km midlevel lapse rates at JAX/CHS, but notably weaker over the FL Peninsula where surface-based parcels are less inhibited. Latest radar data suggests the strongest updrafts should continue along the southern influence of the upper trough where surface-based buoyancy supports robust updrafts -- namely southern GA northern FL. Even so, most of this activity has not produced severe wind/hail and any supercell structures are notably weak. Even so, strong shear will continue to support the potential for robust updrafts, though boundary-layer recovery may struggle to reach levels necessary for widespread, organized updrafts. ..Darrow.. 01/13/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0639 PM CST Fri Jan 12 2024 Valid 130100Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHEASTERN US... ...SUMMARY... Isolated damaging winds and perhaps a tornado remain possible tonight across portions of the southeastern US. ...01z Update... Primary upper low is shifting northeast toward southern WI early this evening as main midlevel jet translates across the TN Valley. With the upper system now focused over the Great Lakes, trailing cold front is less dynamically focused but should still remain the primary mechanism for convective development this evening. 00z soundings ahead of the front exhibit around 6.5-7C/km midlevel lapse rates at JAX/CHS, but notably weaker over the FL Peninsula where surface-based parcels are less inhibited. Latest radar data suggests the strongest updrafts should continue along the southern influence of the upper trough where surface-based buoyancy supports robust updrafts -- namely southern GA northern FL. Even so, most of this activity has not produced severe wind/hail and any supercell structures are notably weak. Even so, strong shear will continue to support the potential for robust updrafts, though boundary-layer recovery may struggle to reach levels necessary for widespread, organized updrafts. ..Darrow.. 01/13/2024 Read more

MD 0058 CONCERNING HEAVY SNOW FOR PORTIONS OF NORTHERN/CENTRAL LOWER MICHIGAN AND FAR NORTHEAST WISCONSIN
Mesoscale Discussion 0058 NWS Storm Prediction Center Norman OK 0547 PM CST Fri Jan 12 2024 Areas affected...Portions of northern/central Lower Michigan and far northeast Wisconsin Concerning...Heavy snow Valid 122347Z - 130345Z SUMMARY...Heavy snow with rates of 1 to locally 2 in/hr will continue spreading northward across Lower MI and northeast WI this evening. DISCUSSION...A fairly expansive swath of heavy snow with rates near 1 in/hr are ongoing across much of Lower MI this evening, largely driven by a deep band of isentropic ascent ahead of a 984 mb surface cyclone currently over northeast IL. Latest web cams across Lower MI show snow sticking to roadways as surface temperatures continue to nocturnally cool. Over the next few hours, the strong isentropic ascent (50-60-kt 1-2 km cross-isotherm flow per regional VWP) will continue northward in tandem with the northeastward-moving surface cyclone. This will occur as ascent in the left exit region of a robust southwesterly jet streak overspreads the area. The strengthening deep-layer ascent coupled with increasingly cold thermodynamic profiles with northward extent will continue to support heavy snow with rates of 1-2 in/hr given a deep/saturated dendritic growth zone. The best chance for localized 2 in/hr rates could develop across northeastern Lower MI from 00-04Z, where colder temperatures and stronger ascent should overlap for a couple hours (supported by the latest high-resolution guidance). In addition, a modest pressure gradient and related breezy surface winds should continue to favor visibility reductions to 0.25 miles in the heavier bursts of snow. ..Weinman.. 01/12/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DTX...APX...GRR...MQT...GRB...MKX... LAT...LON 42828544 43098686 43428775 43928809 44788799 45568719 45918639 45978545 45868442 45598376 45088307 44198258 43668248 43008299 42778397 42828544 Read more

MD 0056 CONCERNING BLIZZARD FOR IOWA
Mesoscale Discussion 0056 NWS Storm Prediction Center Norman OK 0229 PM CST Fri Jan 12 2024 Areas affected...Iowa Concerning...Blizzard Valid 122029Z - 130030Z SUMMARY...Blizzard conditions will become more widespread through the afternoon and evening across portions of Iowa. DISCUSSION...The primary surface low continues to track to the northeast with recent surface observations/analyses depicting the center of the low over central IL. To the west/northwest of the low, a cold air mass continues to push southward across IA. Gradient winds have slowly been increasing with the approach and deepening of the low. While sustained winds have largely remained below 35 mph thus far, frequent gusts between 30-40 mph have been observed across IA with subsequent visibility reductions down to 1/4 mile. Winds are forecast to peak around 00 UTC with frequent gusts between 35-45 mph likely. Although snowfall should gradually diminish through the evening, a fresh, 2+ inch snow pack is in place across much of the state per recent LSRs. Blowing snow model output indicates that this combination of winds, a fresh/deep snow pack, and temperatures in the teens will support scattered to widespread blizzard conditions with prolonged visibility reductions of 1/4 mile or less. Based on recent hi-res guidance, portions of central/eastern IA may see wind gusts up to 50-55 mph over a 4-10 inch deep snow pack, resulting in a corridor of fairly intense blizzard conditions with near-zero visibilities possible. ..Moore.. 01/12/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DVN...ARX...DMX...EAX...FSD...OAX... LAT...LON 42569536 42099566 41539565 41269543 40969480 40269277 40339192 40639135 40879120 41539128 42179129 42469118 42879110 43299131 43509162 43499262 43369346 43029467 42569536 Read more

No watches are valid as of Fri Jan 12 23:50:02 UTC 2024.

MD 0057 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR MUCH OF SOUTHWEST GEORGIA AND PARTS OF THE FLORIDA PANHANDLE
Mesoscale Discussion 0057 NWS Storm Prediction Center Norman OK 0318 PM CST Fri Jan 12 2024 Areas affected...much of southwest Georgia and parts of the Florida Panhandle Concerning...Severe potential...Watch unlikely Valid 122118Z - 122345Z Probability of Watch Issuance...20 percent SUMMARY...Isolated strong storms cannot be ruled out over the next couple hours, from the Florida Panhandle into southwest Georgia. DISCUSSION...Surface analysis shows a dryline roughly bisecting AL and extending into the northern Gulf of Mexico, with a warm front from southern AL into northern FL. Relatively cool air remains in place over the TLH area, with warming noted into southwest GA. A small plume of 66-70 F dewpoints currently exist over the western FL Panhandle into far southwest GA, resulting in around 1000 J/kg MLCAPE. Strong wind fields remain over the area, with 850 mb southwesterlies over 60 kt. Boundary-layer mixing is aiding surface gusts of 25-35 kt with gradual theta-e recovery. Veering and increasing winds with height still conditionally support supercell and tornado risk, but overall ascent remains limited. As such, the area is being monitored for more robust storm initiation over the next few hours. A better chance at isolated severe storms would exist should the cool air over the FL Panhandle/southern GA finally modify. ..Jewell/Thompson.. 01/12/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FFC...TAE... LAT...LON 30278391 30138447 30278523 30448558 30688568 30998548 31678503 32368460 32438416 32278360 31718334 31118336 30758348 30278391 Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0249 PM CST Fri Jan 12 2024 Valid 141200Z - 201200Z A series of mid-level troughs will traverse the CONUS during the upcoming week, reinforcing an arctic surface airmass over much of the CONUS and limiting wildfire-spread potential in most places. One localized exception would be portions of Far West Texas, which will experience dry downslope flow early in the week amid marginally receptive fuels. If guidance consensus continues to suggest that 15+ mph sustained westerly winds will develop during the afternoon, Elevated highlights may need to be added in the Days 1-2 period. Medium-range guidance also depicts surface lee troughing along the southern High Plains between mid-level troughs on Day 6/Wednesday, which may promote dry downslope flow. However, too much uncertainty remains this far in advance in terms of fuel receptiveness or best area of overlapping winds/RH to deduce with confidence whether Elevated-equivalent conditions will occur. ..Squitieri.. 01/12/2024 ...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 0249 PM CST Fri Jan 12 2024 Valid 141200Z - 201200Z A series of mid-level troughs will traverse the CONUS during the upcoming week, reinforcing an arctic surface airmass over much of the CONUS and limiting wildfire-spread potential in most places. One localized exception would be portions of Far West Texas, which will experience dry downslope flow early in the week amid marginally receptive fuels. If guidance consensus continues to suggest that 15+ mph sustained westerly winds will develop during the afternoon, Elevated highlights may need to be added in the Days 1-2 period. Medium-range guidance also depicts surface lee troughing along the southern High Plains between mid-level troughs on Day 6/Wednesday, which may promote dry downslope flow. However, too much uncertainty remains this far in advance in terms of fuel receptiveness or best area of overlapping winds/RH to deduce with confidence whether Elevated-equivalent conditions will occur. ..Squitieri.. 01/12/2024 ...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 0249 PM CST Fri Jan 12 2024 Valid 141200Z - 201200Z A series of mid-level troughs will traverse the CONUS during the upcoming week, reinforcing an arctic surface airmass over much of the CONUS and limiting wildfire-spread potential in most places. One localized exception would be portions of Far West Texas, which will experience dry downslope flow early in the week amid marginally receptive fuels. If guidance consensus continues to suggest that 15+ mph sustained westerly winds will develop during the afternoon, Elevated highlights may need to be added in the Days 1-2 period. Medium-range guidance also depicts surface lee troughing along the southern High Plains between mid-level troughs on Day 6/Wednesday, which may promote dry downslope flow. However, too much uncertainty remains this far in advance in terms of fuel receptiveness or best area of overlapping winds/RH to deduce with confidence whether Elevated-equivalent conditions will occur. ..Squitieri.. 01/12/2024 ...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 0249 PM CST Fri Jan 12 2024 Valid 141200Z - 201200Z A series of mid-level troughs will traverse the CONUS during the upcoming week, reinforcing an arctic surface airmass over much of the CONUS and limiting wildfire-spread potential in most places. One localized exception would be portions of Far West Texas, which will experience dry downslope flow early in the week amid marginally receptive fuels. If guidance consensus continues to suggest that 15+ mph sustained westerly winds will develop during the afternoon, Elevated highlights may need to be added in the Days 1-2 period. Medium-range guidance also depicts surface lee troughing along the southern High Plains between mid-level troughs on Day 6/Wednesday, which may promote dry downslope flow. However, too much uncertainty remains this far in advance in terms of fuel receptiveness or best area of overlapping winds/RH to deduce with confidence whether Elevated-equivalent conditions will occur. ..Squitieri.. 01/12/2024 ...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 0249 PM CST Fri Jan 12 2024 Valid 141200Z - 201200Z A series of mid-level troughs will traverse the CONUS during the upcoming week, reinforcing an arctic surface airmass over much of the CONUS and limiting wildfire-spread potential in most places. One localized exception would be portions of Far West Texas, which will experience dry downslope flow early in the week amid marginally receptive fuels. If guidance consensus continues to suggest that 15+ mph sustained westerly winds will develop during the afternoon, Elevated highlights may need to be added in the Days 1-2 period. Medium-range guidance also depicts surface lee troughing along the southern High Plains between mid-level troughs on Day 6/Wednesday, which may promote dry downslope flow. However, too much uncertainty remains this far in advance in terms of fuel receptiveness or best area of overlapping winds/RH to deduce with confidence whether Elevated-equivalent conditions will occur. ..Squitieri.. 01/12/2024 ...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 0249 PM CST Fri Jan 12 2024 Valid 141200Z - 201200Z A series of mid-level troughs will traverse the CONUS during the upcoming week, reinforcing an arctic surface airmass over much of the CONUS and limiting wildfire-spread potential in most places. One localized exception would be portions of Far West Texas, which will experience dry downslope flow early in the week amid marginally receptive fuels. If guidance consensus continues to suggest that 15+ mph sustained westerly winds will develop during the afternoon, Elevated highlights may need to be added in the Days 1-2 period. Medium-range guidance also depicts surface lee troughing along the southern High Plains between mid-level troughs on Day 6/Wednesday, which may promote dry downslope flow. However, too much uncertainty remains this far in advance in terms of fuel receptiveness or best area of overlapping winds/RH to deduce with confidence whether Elevated-equivalent conditions will occur. ..Squitieri.. 01/12/2024 ...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 0249 PM CST Fri Jan 12 2024 Valid 141200Z - 201200Z A series of mid-level troughs will traverse the CONUS during the upcoming week, reinforcing an arctic surface airmass over much of the CONUS and limiting wildfire-spread potential in most places. One localized exception would be portions of Far West Texas, which will experience dry downslope flow early in the week amid marginally receptive fuels. If guidance consensus continues to suggest that 15+ mph sustained westerly winds will develop during the afternoon, Elevated highlights may need to be added in the Days 1-2 period. Medium-range guidance also depicts surface lee troughing along the southern High Plains between mid-level troughs on Day 6/Wednesday, which may promote dry downslope flow. However, too much uncertainty remains this far in advance in terms of fuel receptiveness or best area of overlapping winds/RH to deduce with confidence whether Elevated-equivalent conditions will occur. ..Squitieri.. 01/12/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 0055 CONCERNING HEAVY SNOW FOR EASTERN IOWA INTO NORTHERN ILLINOIS AND SOUTHERN WISCONSIN
Mesoscale Discussion 0055 NWS Storm Prediction Center Norman OK 1024 AM CST Fri Jan 12 2024 Areas affected...Eastern Iowa into northern Illinois and southern Wisconsin Concerning...Heavy snow Valid 121624Z - 122030Z SUMMARY...Areas of 1+ in/hour snowfall rates appear probable within a broader swath of moderate snowfall across eastern Iowa into southern Wisconsin and northern Illinois through early afternoon. DISCUSSION...Surface observations over the past couple of hours have been reporting visibilities between 1/4 to 1/2 mile from eastern IA into southern WI and far northern IL. Sustained 20-25 knot winds across eastern IA are supporting areas of blowing snow per blowing snow model output and web cams, which is contributing to the reduced visibilities. Further east into WI/IL, weaker winds suggest moderate to heavy snowfall rates are the primary contributors to the reduced visibility. Regional radar mosaics support this idea with relatively short (~1 hour) snow bands noted over the past hour. These bands appear to be mainly driven by strong warm air advection within the 0-2 km layer based on regional VWP observations. Despite the magnitude of the warm air advection, 12 UTC and recent RAP forecast soundings suggest this ascent is displaced from the DGZ within the 3-4 km layer. This will modulate snowfall rates across the broader region, but heavier snowfall rates at/above 1 in/hour will be possible within the transient snow bands. This trend should continue through early/mid afternoon before stronger ascent within the warm advection regime shifts northeast with the synoptic low. ..Moore.. 01/12/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...GRB...LOT...MKX...DVN...ARX...DMX... LAT...LON 42298784 42288865 42098933 41709012 41229071 40879134 40829179 40969224 41859276 42199268 42539238 43209128 44258906 44358860 44458819 44478769 44388732 43928757 43318770 42818768 42488762 42298784 Read more