Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 01/06/21

Area Forecast Discussion...UPDATED
National Weather Service Albuquerque NM
834 PM MST Tue Jan 5 2021 .UPDATE... Last several runs of the HRRR and RAP13 indicate potential for a period of strong north winds later tonight over far northeast NM, then again late Wednesday morning before tapering off. Also, while still relatively small, localized higher QPF/pops are indicated as well, although resulting snowfall will likely be around an inch or so if the models are close. Cloud cover looks to be more extensive over eastern NM as well. Went ahead with a wind advisory, and along with the ZFP, those products are already out. && .PREV DISCUSSION...501 PM MST Tue Jan 5 2021... .AVIATION... 00Z TAF CYCLE Gusty west to northwest winds to around 35 or 40kt along the central mt chain and portions of ern NM to diminish aft 06/02Z while becoming more nly. Sfc low over far se CO at 23Z to slide to the se, with cold frontal boundary pushing into ne NM on gusty nly wind to around 40kt. Lcl MVFR cigs/vsbys obscuring terrain in -shsn over far ne NM to develop around 06/02Z impacting KRTN to KCAO through 06/12Z, while nly wind shift reaches KCVS by around 05Z. Improving conditions over ern NM aft 06/15Z. && .PREV DISCUSSION...340 PM MST Tue Jan 5 2021... .SYNOPSIS... Expect strong winds to gradually weaken this evening, although northerly gusty conditions will persist tonight along the Oklahoma and Texas borders as a backdoor front slides southward through the region. Quiet weather conditions are expected for Wednesday through Friday. The next storm system is forecast to impact portions of New Mexico on Saturday through Sunday morning. It appears this feature will bring precipitation in the form of light to moderate snow over the northern mountains as well as the eastern plains of New Mexico. Activity may mix with rain over the southeast. Colder temperatures and gusty winds will also accompany this storm system. It`s still a little too early to know the exact impacts from this storm, however those with travel plans this weekend are encouraged to stay abreast to the latest forecasts. && .DISCUSSION... SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT)... Winds are expected to diminish in the wake of the Pacific front that passed through earlier today, and as such will allow the Wind Advisory to expire on schedule at 01Z. Even drier air will be advected into the Land of Enchantment behind the front with clearing skies. Winds will decouple by the evening, allowing strong valley inversions to setup tonight across western and northern NM. Cooler overnight temperatures are expected for most locales, though these readings will still be near to above normal. A backdoor front will progress south across the eastern plains, bringing breezy northerly winds to areas along the OK/TX border. Temperatures on Wednesday will be cooler areawide, with highs across the eastern plains reaching 10 to 15F below today`s readings. Breezy conditions will persist along the TX border behind the backdoor front into the afternoon, due to amplified flow aloft. Elsewhere, a quiet day is in store with dry conditions and sunny skies. 12 LONG TERM...(THURSDAY THROUGH TUESDAY)... A low-amplitude ridge axis will gradually roll east of the Land of Enchantment for Thursday with high temperatures near/slightly above average. Meanwhile, a relatively weak shortwave trough originating from the PacNW will progress its way across the central Rockies for Thursday/Thursday night. It will bring nothing more than some high clouds across the region, but expect a backdoor front to offer weak cold air advection in its wake Thursday night and Friday. This will push high temperatures a tad below normal in the ern plains for the last day of the work week. Expect a rinse and repeat weather pattern with a relatively low- amplitude ridge traversing the state on Friday. Yet another, albeit stronger piece of energy will dive southeast toward the central and southern Rockies. This feature will bring greater hopes for precip chances early Saturday through Sunday morning as it tracks through northern and central NM. Surprisingly, there is good agreement on the placement, strength and timing of this feature between the GFS and ECWMF deterministic and ensemble members. A weak low could form, but will likely be short-lived in the fast-moving flow aloft. There is one outlier, the deterministic Canadian which has a well-defined closed low and places it on a trajectory from northern AZ through southern NM, which is a bit further west than the GFS/ECMWF. Will not entertain at this time, but if this solution materializes, then winter weather impacts could be felt further west over western and central NM. Regardless, another front will sweep through the region with upslope flow being in phase with the upper level dynamics, and this will bring a decent shot for precipitation over the ern plains. Unfortunately, the speed of this system may be a limiting factor for significant/major snowfall totals. The barrage of upper level systems continues with a third feature embedded within north-northwest flow, albeit weaker and drier, will swing through the state on Monday. DPorter && .FIRE WEATHER... Winds will be diminishing into the eve hours, with the exception of near and along the OK/TX borders, as a backdoor front descends across the eastern plains Tuesday night. Poor ventilation can be expected on Wednesday, with the exception of the far eastern plains where mixing heights will be higher alongside stronger transport winds. Breezy northerly winds will persist across the far eastern plains throughout the day on Wednesday, leading to brief elevated fire weather conditions near the OK/TX borders. Dry conditions are expected to prevail on Thursday, with temperatures rebounding. Widespread poor ventilation rates can be expected Thursday and Friday. The next chance for wetting precip arrives Saturday as an upper level system and associated cold front moves through the state. The greatest potential for accumulating snowfall will be favored over the northern mountains and the eastern plains. 12 && .ABQ WATCHES/WARNINGS/ADVISORIES... Wind Advisory until noon MST Wednesday for the following zones... NMZ227-228-230. && $$
Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
918 PM CST Tue Jan 5 2021 .UPDATE... Issued at 918 PM CST Tue Jan 5 2021 Upper level low pressure area pivoting in northeast sd late this evening with really good returns on radar. Webcams and surface obs showing snow along with rain with these returns. The issue for tonight will be the extent of the radar returns and intensity along with the time of changeover to all snow. Expect the changeover to occur as the temperatures cool down with the precipitation by around midnight or shortly after. The initial rainfall and warmer temperatures will affect the snowfall amounts. Have lowered snowfall amounts a little already. Some freezing rain is still also possible west of the James Valley tonight. Made several changes to the forecast. UPDATE Issued at 545 PM CST Tue Jan 5 2021 00z aviation discussion updated below. && .SHORT TERM...(This Evening through Wednesday Night) Issued at 251 PM CST Tue Jan 5 2021 An approaching sfc trough and mid level low will bring some snow to the region tonight. At the moment the latest guidance keeps the heaviest snow potential in and around the James Valley in the axis of the trough. Tossed the RAP out for this forecast area given its penchant for too much fzra even with moisture in the snow growth region and profiles all below freezing by late evening. Southerly flow ahead of the low has primed the region with increasing mid level moisture. Prior to full saturation at the lower levels there could be some freezing drizzle that mixes in, especially along the I- 90 corridor. Areas with higher omega and better forcing with saturated profiles into the snow growth region seem to be focused from Brown to Marshall/Day counties. Added a winter weather advisory where 2 to 4 inches is likely though confidence is not high on the exact placement of highest snow as it will be in a narrow band. As the snow exits from north to south on Wednesday, there could be some periods of freezing drizzle mixed in. Generally leaned toward 75th percentile snow accumulations with higher than NBM SLRs since winds will not be that strong and temps will fall below 30F tonight. Couldn`t justify a 7:1 ratio in those conditions as the NBM had. .LONG TERM...(Thursday through Tuesday) Issued at 251 PM CST Tue Jan 5 2021 Dry conditions start the long term, however increasing confidence of a secondary wave moving into the region Friday, bringing light accumulation chances. Upper flow looks to remain weak during the out period which will limit moisture potential. Messy upper flow will also bring multiple waves throughout the out period, however low confidence of any precipitation with these disturbances aside from the light accumulation potential on Friday. While temperatures do cool down slightly moving into the weekend, overall pattern should keep highs slightly above normal through the forecast period. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday Evening) Issued at 545 PM CST Tue Jan 5 2021 Terminals KABR,KATY,KPIR,KMBG A slow moving upper level low pressure area over South Dakota will bring mainly snow to ABR and ATY tonight into Wednesday. There could also be some light rain or freezing rain at times. IFR/MVFR ceilings and vsbys are expected at ABR and ATY through Wednesday afternoon. Otherwise, VFR conditions at PIR and MBG will become MVFR tonight and remain through Wednesday as low clouds move in. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...Winter Weather Advisory until noon CST Wednesday for SDZ005>007- 010-011-017>019. MN...None. && $$ UPDATE...Mohr SHORT TERM...Wise LONG TERM...Dye AVIATION...Mohr
Area Forecast Discussion
National Weather Service Bismarck ND
941 PM CST Tue Jan 5 2021 .UPDATE... Issued at 936 PM CST Tue Jan 5 2021 Increased the rain, freezing rain, snow chances across the James River Valley. Models performed badly with this event, with much more rain and freezing rain at the onset of this event than what was depicted. We are finally changing over to snow, but not before a tenth of an inch or more of rain/freezing rain fell across Dickey, LaMoure, southern Stutsman, and eastern Logan and McIntosh counties. It goes without saying travel is hazardous for these locations. At this point, will stick with the special weather statement and elevate the expected impacts. UPDATE Issued at 713 PM CST Tue Jan 5 2021 The forecast for tonight remains on track. Increased POPs across my southeast based on latest radar loop and short term guidance. Will keep a wintry mix through the first few hours of this event before all precipitation changes over to snow. Will also maintain the SPS as is. && .SHORT TERM...(This evening through Wednesday) Issued at 333 PM CST Tue Jan 5 2021 The short term forecast is highlighted by accumulating snow in the James River Valley tonight into Wednesday morning. This afternoon, a shortwave upper trough was located over the Northern Rockies, with two surface low pressures in the surrounding area that will influence our forecast area through the short term. One is located in central Saskatchewan, with a trailing frontal boundary that is just getting to the western edge of the forecast area as of 20 UTC. Weak radar returns have been persisting all day along and ahead of this front, with some light rain reported in the northwest and some light snow grains observed in north Bismarck, but otherwise a significant dry layer in the low and mid levels has kept most precipitation from reaching the surface. A chance of rain and snow will follow the front as it pushes east through the afternoon and evening, but overall minimal precipitation is expected with this feature. The second surface low is located in southwest South Dakota, and is expected to move northeast through South Dakota this evening and overnight. This is where our focus is in terms of accumulating snow, with precipitation wrapping around the north side of the low in line with an upper vort max. Current forecast has the highest amounts of 2-4 inches in Dickey and LaMoure Counties, with 1-2 inches in Stutsman, Logan, and McIntosh, and less than an inch elsewhere. Some of the 24-hour postage stamps from the 12 UTC HREF highlight the potential for higher snowfall amounts, on the order of 4-6 inches of accumulation. Not too strong of a signal in high-res guidance for this kind of heavy banded snow, with a modest band of frontogenetical forcing in the latest RAP run and moderately strong omega overnight (depending on what guidance you choose), but we`re not quite confident enough to have that high of snow amounts in the forecast, although it is possible. Dry air has been the main concern with this system, with guidance not showing saturation in the lower levels until after 3 UTC. Any delay in this could lessen snow accumulations a bit. Wasn`t quite enough snow to go for an advisory, but will put out an SPS to message the snow potential. There also is the potential for some light freezing rain in the James River Valley this evening with a small warm nose aloft, but with BUFKIT soundings only showing this potential for an hour or two, and still concerns with dry air, decided to keep any ice accumulations very minimal to none, but will message the possibility. Snow will taper off Wednesday morning in the James River Valley, with some patchy fog from the north-central through the James River Valley. Skies will clear in the west and parts of the central, but the James River Valley will likely stay overcast through the day. Highs will generally be in the 30s, with lower 40s possible in the southwest. .LONG TERM...(Wednesday night through Tuesday) Issued at 333 PM CST Tue Jan 5 2021 The extended forecast is highlighted by continued above average temperatures, with a chance for snow Thursday night into Friday. Quiet weather won`t last long as the chance for snow returns Thursday night with another shortwave approaching the region. Overall, the forcing with this system looks only marginal, so current thought is it will be more of a longer duration but light snow event. Still quite a large spread in ensemble guidance for this chance of snow, but a general spatial pattern is emerging when looking at individual ensemble members, with light accumulations extending through most of western and central North Dakota, and a swath of slightly higher totals embedded from the southwest to the north central. Both GEFS and WPC Super Ensemble plumes have some slight clustering from 0-0.10" of QPF, especially at Bismarck and Jamestown. However, both of these as well as Williston, Dickinson, and Minot all still have a wide range of solutions up to 0.40" of QPF, so there is certainly potential for a few inches of snow accumulation. As we head into the weekend, some light snow might linger into Saturday, but not seeing much in terms of precipitation looking into the start of next work week. Temperatures should continue to stay above average, with highs generally in the mid 20s to upper 30s, before CIPs analogs are favoring a transition to colder temperatures across the Northern Plains in the 12-14 day range. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 713 PM CST Tue Jan 5 2021 Mainly VFR conditions expected through the TAF period except for at KJMS. Chance of light precipitation across central ND this evening mainly in the form of light snow. Across the James River Valley, accumulating snow is expected tonight, along with an hour or two of mixed precipitation. Reduced visibilities from fog and IFR ceilings also expected at KJMS after 03Z and continuing through the end of the TAF period. MVFR ceilings are possible along the cold front that will push through, beginning in the northwest after 00Z. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...NH SHORT TERM...MJ LONG TERM...MJ AVIATION...NH