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FXUS63 KABR 281510 AAB AFDABR Area Forecast Discussion...UPDATED National Weather Service Aberdeen SD 1010 AM CDT Thu Mar 28 2024 .KEY MESSAGES... - A disturbance moving through the region late tonight into Friday will deliver a 30-50% chance for rain and/or freezing rain. Up to a few hundredths of ice accumulation will be possible. - Precipitation chances increase this weekend, perhaps in two waves, late Saturday/Saturday night, then again late Sunday through Monday. Early indications suggest a "less than 6 inch type outcome" for the time being. - Warming temperatures moving in by mid-week next week, with 40s, 50s, and perhaps even 60s (central SD on Wed) moving into the region. && .UPDATE... Issued at 1010 AM CDT Thu Mar 28 2024 The forecast remains on track this morning. No major changes are planned. && .SHORT TERM /TODAY THROUGH FRIDAY AFTERNOON/... Issued at 445 AM CDT Thu Mar 28 2024 We'll be able to squeak out another relatively quiet day weather- wise today before a disturbance moves into our region toward the latter half of the period and generate some precip chances for parts of the forecast area. High pressure will gradually shift east and southeast of our area today while a low pressure trough continues to organize across the Rockies and Northern High Plains. With a ridge of high pressure aloft, we can expect a fair amount of sunshine during the day, perhaps high clouds filter out some of that sunshine this afternoon. Warmer daytime highs are expected today, with eastern zones the coolest thanks to thicker snow cover. A tighter pressure gradient develops this afternoon across the western and central Dakotas between the high to the east and the trough to the west. Increasing southeast breezes gusting up around 30 mph will be possible across the Missouri Valley. Clouds will increase tonight as a sfc trough shifts eastward across the Dakotas. The upper ridge will give way to an upper trough lifting northeast out of the Rockies and Northern High Plains. We anticipate light precipitation to develop and shift east- northeastward across our forecast area tonight into Friday. Models seem to be in agreement on the core of this disturbance to pivot out of Montana and into North Dakota keeping the focus for steadier QPF to our north. BUFKIT soundings do show a warm nose(above freezing) aloft, just off the surface with temperatures at or colder than freezing at the surface. That warm nose will take some time to saturate, but eventually it looks to and we should see a period of freezing rain spread across the forecast area late tonight into Friday morning. WPC QPF and NBM generally are in the same camp indicating up to a few hundredths of ice accumulation will be possible across the northern tier of our CWA. && .LONG TERM /FRIDAY EVENING THROUGH WEDNESDAY/... Issued at 445 AM CDT Thu Mar 28 2024 Surface high pressure will be moving over the region Friday night through much of the day Saturday, before pushing east Saturday night as the first wave of precipitation chances approach. In regards to the precipitation over the weekend into Monday, latest deterministic solutions are starting to show this in two waves now, the first being Saturday night, with the more meaningful onset of precip late Sunday through Monday. Inherited NBM PoPs, as well as ensemble probs for measurable still fail to adequately portray this given their more blended/averaged feel. Will have to watch to see if this a trend that holds. By 00Z Tuesday, probability of exceedance for accumulated snowfall greater than 3 inches (assuming 10:1 ratios) are running from around 40-60% across central SD, with lesser amounts around 40% or below further east. Snowfall means amongst the GEFS/ENS/GEPS are running around 2 to 4 inches by 00Z Tuesday, with some higher end scenarios (75th percentiles) on the order of 4 to 6 inches (mainly over central SD). Looking ahead to mid-week next week, we see signs in the cluster output of overall ridging trying to build across the Northern Plains. There still area some glaring differences in the upper level patterns amongst the four clusters in the 00Z Thurs - 00Z Fri period. Clusters 2 and 3 (with 20% and 19% membership respectively) hold on to a much deeper and slower moving trough over the Great Lakes, which in turn show a large ridge amplification over the High/Northern Plains. Cluster 1, which has the largest membership at 43%, shows a more flattened upper level pattern over the region, but still mild nonetheless. The differences can be seen in 850mb temps as well, with the more amplified ridge scenario running between +7C to +12C across the CWA. Grand Ensemble of the clusters are generally between +3C and +7C from east to west across the CWA. All that said, the overall ridging moving in will mean a warm up into the 40s and 50s likely, perhaps even 60s on Wednesday across central SD according to the inherited NBM temperatures. && .AVIATION /12Z TAFS THROUGH 12Z FRIDAY/... Issued at 626 AM CDT Thu Mar 28 2024 Terminals KABR,KATY,KPIR,KMBG Potential exists this morning for BR across the KATY region, so inserted a TEMPO mention of this. Otherwise, VFR conditions can be expected through much of the TAF period, although MVFR CIGs are forecast to begin moving into KMBG towards the end of the period. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. && $$ UPDATE...Wise SHORT TERM...Vipond LONG TERM...TMT AVIATION...TMT