Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 03/14/22


Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
912 PM CDT Sun Mar 13 2022 .UPDATE... Issued at 857 PM CDT Sun Mar 13 2022 Continuing to watch the evolution of the storm system that will move through the region overnight into Monday morning. Been seeing echoes across the northeast CWA for the past few hours, but cannot find any obs or web cams that reveal light snow. BUFKIT soundings and 00Z RAOB sounding from KABR indicate quite a bit of dry air still to overcome. Although, it is snowing just across the border in ND. What`s interesting is the large differences noted in regards to how quickly this dry layer moistens enough to support snow to the surface. RAP is quickly moistening the profile in the next couple hours, while other models hold off for several more hours. At some point later tonight, still expect to see snow eventually affect the northeast CWA. Looking back to the west, seeing another area of precipitation under the main mid-level circulation associated with the shortwave. Interesting to note that some hi-res models bring this area of precip into central/north central SD later this evening. Previous forecast did not have much in the way of POPs over central SD, so added chances for the time being. May have to go even higher after watching radar trends over the next couple hours. && .SHORT TERM...(This Evening through Monday Night) Issued at 314 PM CDT Sun Mar 13 2022 A low pressure system is slated to move into south central SD this evening. This system will push warm air ahead of it creating a sharp thermal gradient along the ND/SD border and into west central MN tonight. It`s along this thermal boundary, supported by a shortwave trough, that some light snow will develop. There will likely be some banding with locally higher amounts associated with this system. However, models have trended a bit farther north with the banding potential, keeping the heaviest amounts over ND and into MN north of this cwa. That trend would keep the best chances for seeing greater than an inch of snow to along the Sisseton Hills and into west central MN. Toward morning, BUFKIT profiles continue to indicate loss of moisture in the snow growth region. There`s still some uncertainty regarding whether or not the cloud layer will then be deep enough to support freezing drizzle or if precip will simply come to an end. Best guess is that areas from the James Valley east to the Sisseton Hills could see an hour or two of freezing drizzle or freezing drizzle mixing with light snow. What complicates the forecast is the timing, as some of this fzdz may occur right around the morning commute before precip tapers off. Warm air will advect in from the west again on Monday, so while highs may only top out in the lower 30s in the northeastern forecast area, areas west river will see highs around 50 degrees. High pressure over the northeast will hold off any good mixing through the day. .LONG TERM...(Tuesday through Sunday) Issued at 314 PM CDT Sun Mar 13 2022 The overarching long term pattern remains fairly progressive, and yet the region seems to dodge any of the larger weather systems tracking across the plains. Therefore the main forecast concerns generally revolve around winds and temperatures. The region will be in a warm air advection pattern, out ahead of a weak surface trough, Tuesday. A south to southwest mixing wind and generally partly cloudy to sunny skies should result in favorable conditions for afternoon heating. Ensemble spread remains quite high for MaxT`s Tuesday, especially across northeast South Dakota. Did trend the baseline blended guidance toward the warmer solutions. Highest uncertainty is across the snow covered regions of northeast South Dakota and west central Minnesota. The trough/cold front passes Wednesday. A tightening pressure gradient and deep mixed layer on the back side of this front will result in gusty northwest winds. Again trended the forecast wind speeds above baseline blended guidance. Ensemble spread (across many variables) increases by the end of the workweek due to the model variations relating to a long wave trough tracking across the region. Overall temperatures seem to moderate in the 40s and 50 through the later half of the workweek and into the weekend. && .AVIATION...(For the 00Z TAFS through 00Z Monday Evening) Issued at 628 PM CDT Sun Mar 13 2022 Terminals KABR,KATY,KPIR,KMBG VFR conditions are expected across the region early in the TAF period. Later tonight and into Monday morning, a system will move across the region with CIGs lowering to MVFR or even IFR. Current TAFs show MVFR CIGs, but there are some hints that IFR is possible, so will continue to monitor. Expecting -SN/SN to affect northern SD tonight, and may have to amend to prevailing precip with VSBY restrictions depending on development. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. && $$ UPDATE...TMT SHORT TERM...Wise LONG TERM...Serr AVIATION...TMT
Area Forecast Discussion
National Weather Service Grand Junction CO
524 PM MDT Sun Mar 13 2022 .SHORT TERM...(Tonight through Monday night) Issued at 220 PM MDT Sun Mar 13 2022 Radar returns and local webcams in and around Salt Lake City are showing plenty of low clouds with some rain in the lower elevations and a few snow showers in the higher elevations. This matches up very well with current guidance especially the 15 min HRRR and 3km NAM. This is in response to an approaching trough from the northwest. This guidance does show radar returns blossoming across portions of our CWA from about 4PM onwards. As mentioned, this little system is very quick and the NAM is now showing most precip to be over shortly after midnight whereas the HRRR keeps it going through about 4AM. Some banding looks likely, especially along the surface front, which is when the most intense precip is expected. Snowfall amounts look similar to previous runs with 2 to 4 inches likely, maybe 6 inches or a wee bit more, for the highest peaks. Expect some travel headaches over the usual mountain passes but outside of those areas, impacts won`t be too widespread so opted for no highlights. By Monday morning, the storm and precip will be all but over with only a few, very isolated, mountain showers by lingering. In fact, by noon Monday, mostly sunny skies will be the rule. Winds will shift to northerly once the trough moves through but will quickly become westerly as the next ridge builds in. This means a dip in high temperatures for Monday but nothing too excessive, 2 to 5 degrees tops. Even so, this will keep highs below seasonal averages. .LONG TERM...(Tuesday through Sunday) Issued at 220 PM MDT Sun Mar 13 2022 A quiet start to the extended period is still looking good Tuesday with ridging extending from Mexico to Canada across the Rockies. Temperatures are expected to remain mostly normal across western Colorado and eastern Utah under zonal flow this week with no deep intrusions of colder air expected. Some extended numerical guidance wants to put a six in the temperatures of the low valleys of western Colorado late in the week. Climatologically, this is not hard to believe. The third week of March finds us inching closer to April and thus, warmer days. The key weather event of the week still looks like an upper level trough moving across the intermountain west Wednesday morning. EC and GFS are both in relative agreement that precipitation will enter the CWA by daybreak Wednesday and hold on in some capacity through Thursday. Without getting into details that will command closer analysis, it does look like we will see more snow in the mountains out of this system versus the previous event based solely on duration of the event. It doesn`t look like precipitable water is exceptionally large according to models, so will hold off on getting carried away with snowfall promises. High pressure builds back in Friday morning and persists through Saturday and Sunday, which coincidentally is advertised as the warmest day of the period. The next event looks like it arrives at the close of this extended period Sunday evening. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 524 PM MDT Sun Mar 13 2022 Clouds will continue lowering resulting in ceilings below ILS breakpoints for KRIL, KEGE and KASE later this evening. Light snow has resulted in MVFR conditions at KHDN just before 00Z and this activity will continue into the evening. Similar conditions can be expected later this evening at the remaining western Colorado TAF sites. Conditions are expected to rapidly improve at most sites after 12Z with some gusty winds behind the front in KTEX, KDRO, and KGUC. Mountain sites can expect a few stray clouds into 18Z. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...None. UT...None. && $$ SHORT TERM...TGR LONG TERM...LTB AVIATION...TGJT
Area Forecast Discussion
National Weather Service Green Bay WI
1016 PM CDT Sun Mar 13 2022 New Information added to update section .UPDATE... Issued at 1005 PM CDT Sun Mar 13 2022 No changes were made to the winter weather headlines. Made some minor adjustments to the forecast through Monday, which raised snow totals slightly within the main band, and tightened up snow gradients on the northern and southern peripheries. Also added some hourly pops during the afternoon to depict the snow band shifting south and weakening with time. There is still a bit of uncertainty on exactly where the west-east oriented frontogenetic snow band will set across north central and far northeast Wisconsin, but still think there is potential for 6+ inches in a narrow band. && .SHORT TERM...Tonight and Monday Issued at 300 PM CDT Sun Mar 13 2022 The latest RAP analysis and satellite/radar imagery show cold advection occurring behind a storm system that dropped 1 to 3 inches of snow last night. Cloud cover has been restricted to north of the HWY 29 corridor which is further into the colder airmass. Some clearing is possible for a time later this afternoon as the colder air starts to retreat to the northeast. Attention then turns to the storm system projected to impact the region on Monday. Snow accumulations, locations, and timing are the main forecast concerns with this system. Tonight...After a period of clearing early this evening, mid and high clouds will rapidly return and lower into the overnight hours. A southern stream impulse will lead to the development of a mid-level convergence zone within a split flow regime that will track across the northern Mississippi Valley and into northern Wisconsin after midnight. A narrow swath of snow within this convergent zone remains expected to push into central WI shortly after 06z, before lifting into northern WI late. Snowfall amounts will be initially light as precip will encounter dry air at onset. Therefore amounts only up to 1 inch will be possible by 12z. Lows will range from the mid teens north to upper 20s south. Monday...Concern is growing for a narrow band of heavy snow across far northern WI. Forcing increases on Monday morning thanks to upper divergence in the right front quad of a 100+ kt jet streak and strengthening mid-level convergence/frontogenesis (fgen). Furthermore, there are signs of a reduce stability and negative EPV above the fgen that could enhance the band of snowfall and lead to high end snowfall rates. Potential also exists for good dendritic snow growth with the strong ascent in the -12C to -18C layer. These indications have led to an increase of accumulations across northern WI. A swath of 4 to 6 inches now appears possible in an axis from Lincoln County to northern Door county. Wouldn`t be surprised of localized amounts of 6+ inches given the favorable environment. On the other hand, still some differences in the higher resolution models where this snow band will set up, which is not surprising given the mesoscale/narrow nature of the band. Compared to the previous forecast, a slight southward shift is apparent. The freezing rain/drizzle threat also appears to have lowered as well. With coordination from surrounding offices, will issue a Winter Weather Advisory starting at 09z tonight over north-central WI, and 12z over far northeast WI. .LONG TERM...Monday Night Through Sunday Issued at 300 PM CDT Sun Mar 13 2022 Southern-stream low pressure will get kicked out to the east on Tuesday as surface-based high pressure ridging builds into northeast Wisconsin. As the ridge moves through and a clipper- type system approaches, southerly winds will develop and temperatures will warm. High temperatures on Wednesday will rise into the 50s at most locations. The clipper low will have limited moisture to work with and any precipitation associated with the system should be light. As the clipper moves east and an associated cold front sweeps through on Thursday, temperatures will trend closer to normal once again. By the weekend, models suggest another low pressure system will aproach the region, this one once again rising up from the south with plenty of potential to tap gulf moisture and deliver heavier precipitation. && .AVIATION...for 00Z TAF Issuance Issued at 638 PM CDT Sun Mar 13 2022 Mid/high clouds will increase ahead of an approaching low pressure system by late this evening. A narrow snow band will push into north-central WI overnight, then lift north and intensify across northern WI Monday morning. IFR/LIFR conditions are expected within the main snowband during the morning and early afternoon, but the band may be quite narrow, with the potential for rapidly varying conditions over a short distance. The snow band is expected to sag south a bit during the late morning and afternoon, before weakening late in the day. It is possible that ATW and MTW may not see any precipitation, but if they do it should be spotty and light. Even so, ceilings should drop to MVFR as northeast winds bring low clouds into the southern part of the forecast area in the late morning and afternoon. && .GRB WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory from 4 AM to 7 PM CDT Monday for WIZ010- 011-018>021. Winter Weather Advisory from 7 AM to 7 PM CDT Monday for WIZ012- 013-022-073. && $$ UPDATE.........Kieckbusch SHORT TERM.....MPC LONG TERM......ML AVIATION.......Kieckbusch
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
1050 PM CDT Sun Mar 13 2022 .SHORT TERM...(This evening through Monday night) Issued at 224 PM CDT Sun Mar 13 2022 Key Messages: - Last round of snow for the foreseeable future arrives tonight across central MN, spreading into northwest WI by Monday morning. 1 to 3 inches expected north of I-94, with 3 or 4 likely in Polk, Barron, and Rusk counties. - Relatively quiet weather for the rest of the week with above normal temperatures and only very small chances for additional precipitation. High clouds are beginning to increase ahead of the next approaching system currently over the Rockies. Temperatures today exceeded expectations by several degrees, especially in the snow-free areas which should be an omen for this week. Clouds will continue to increase this evening with the eastern edges of the developing band of precipitation possibly reaching central MN this evening. The band of snow will stall across central MN and become steadier and heavier overnight while continuing to build east into WI. Locally heavy snow rates are expected under the band, but hi-res guidance suggests it will become the most organized and intense over Rusk, Barron, and Polk counties Monday morning. HREF probs are pretty low (although non- zero) for 1 inch/hr rates in these counties, but this could be the result of differences within its members than the true probability of heavy snow. Overall, guidance is still not perfectly consistent, but the consistency has improved enough for confidence to increase. Raised PoPs to categorical over central MN and western WI and snow totals were also raised a little within the core as was expected. A Winter Weather Advisory will be issued for Polk, Barron, and Rusk counties where 3 to 4 inches are forecast. The western edge of the band will rotate southeast behind the system and likely clip areas farther to the south of the main show, including the Twin Cities, for a time Monday morning. An inch or less is still expected in those areas. Clouds will clear Monday afternoon and conditions will improve rapidly as temperatures rise back to around 40. Light winds and clear skies Monday night will likely send temperatures into the teens across central MN with the lingering snowpack, while areas across southern MN should only drop into the upper 20s. .LONG TERM...(Tuesday through Sunday) Issued at 224 PM CDT Sun Mar 13 2022 Our old friend "the split flow" develops across the CONUS by mid- week and will act to suppress any storm potential for the remainder of the forecast period. What else does the split flow mean for sensible weather in mid-March? Well it`s a not a favorable pattern for significant synoptic scale development. This matches up with the NBM`s PoPs as there are few chances meaningful precipitation in the following week. Another impact of split flow is that the northern stream will prevent any Arctic air masses from dropping south into the Upper Midwest. This will allow a warmer Pacific air mass to move in and support above normal temperatures into next weekend. How warm? High temperatures are trending warmer mid-week and have been bumped up a few degrees across southern MN and western WI to account for the lack of any meaningful snow pack. Tuesday will have a shot at mid 60s in parts of southern MN and upper 50s for the TC metro on Wednesday. Cooler temperatures arrive on Thursday with upper 40s and lower 50s expected into next weekend. A prominent southern stream system should steer south of us for the end of the week with dry weather prevailing into the weekend. To answer the question of "when will we be snow free?"... We should be snow free by the end of the week with the exception being areas that have at least 6+ inches of snow on the ground in Central Minnesota. && .AVIATION...(For the 06Z TAFS through 06Z Monday night) Issued at 1039 PM CDT Sun Mar 13 2022 Still expecting snow late tonight/Monday morning at all terminals but RWF/MKT. Heaviest snow is expected at STC/RNH. For MSP/EAU, both airports look like they will see 2 or 3 hours of moderate to occasionally heavy snow, but there`s still some uncertainty with how long it will take the precip to reach these terminals. The later the precip comes in, the better chance that it comes in more as a ra/sn mix. Models are also in good agreement of a band of MVFR/IFR cigs working across the entire area with the snow, but there`s still quite a bit of spread with how long those cigs linger behind the precip. For now, stayed near a blend of the short term models for going back to VFR, which is a few hours faster than the LAV. KMSP...We look to be honing in on the 15z to 17z window for seeing a quick burst of snow at MSP, with a vis down to 1/2sm not out of the question. This will also happen with an almost pure cross-wind out of the northeast for the main parallels. Skies should clear out by sunset. For late in this period, the HRRR is hinting at the possibility for dense fog to form basically southeast of a RWF/STC line, so that will be something to keep an eye on over the next couple of iterations of the TAF. /OUTLOOK FOR KMSP/ Tue...VFR. Wind S 10-15kts. Wed...VFR. Wind S to W 5-10kts. Thu...VFR. Wind NW 10-15kts. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...None. WI...Winter Weather Advisory from 3 AM to noon CDT Monday for Barron- Polk-Rusk. && $$ SHORT TERM...Borghoff LONG TERM...BPH AVIATION...MPG