Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/10/24


Area Forecast Discussion
National Weather Service La Crosse WI
557 PM CST Sat Nov 9 2024 .KEY MESSAGES... - Rain will continue to move through the region late this afternoon and evening. A second round of rain (with isolated thunder) will move through the region for the morning and early afternoon on Sunday. Rainfall amounts of around 0.25" or less are expected in most locations. - Seasonable to seasonably warm temperatures next week. Rain chances return late Tuesday night and Wednesday. && .DISCUSSION... Issued at 128 PM CST Sat Nov 9 2024 Rest of Today - Sunday: Periodic Showers This Weekend GOES-16 satellite imagery depict a very prominent mid-latitude cyclone centered over portions of the Great Plains this afternoon associated with a uniformly closed low pressure center. As this low continues to eject northeast bound, isentropic lift associated with 700-850mb theta-e advection will continue to instigate showers further northeast throughout the remainder of the afternoon and evening. Overall, guidance has tended to favor lighter amounts with the recent 09.12z HREF only having lower probabilities (0-40%) for amounts over 1/10". That being said, radar trends certainly show pockets of heavier rainfall rates across northeast IA so would not rule out some locally higher amounts of 0.2 to 0.4" with this first round of precipitation. As we move past the evening and into the overnight hours, the band of showers lifts northeast of the region as the recent CAMs continue to indicate minimal precipitation within a relatively weakly forced regime overnight ahead of the low pressure center. Eventually towards daybreak on Sunday, the closed low moves overhead bringing additional chances for precipitation with the 09.12z HREF having slightly higher probabilities (60-80%) of over 1/10" of rain during the morning hours. With some weak instability present in the long- range HRRR soundings, would not rule out a rumble of thunder or two. Overall though, expecting rainfall amounts from now through Sunday to be generally around 0.25" or less with locally higher amounts possible within more robust showers and any storms. Sunday night into the workweek: Sunday night into Monday, a shortwave trough is forecast to rotate through the U.P. of Michigan. At this time, the HREF is mainly dry, however a few rain mixed with snow showers could clip parts of north central Wisconsin. 09.12Z HREF has a zero joint probability of 850mb temperatures dropping below 0 deg C. and a trace or more of precipitation, however by 15/18Z, the 09.00 deterministic models do cool 0 to 5 below zero north of Black River Falls. HREF probabilities through 12Z Monday for a trace of precipitation are 10 to 50%, but only 0 to 30% for 0.01. Lows have cooled a few degrees from the previous forecast and are currently forecast to range from the mid 30s north of BCK northward to lower 40s Monday morning, if the cooling occurs earlier or if any precipitation is falling, mixed precipitation could occur. It will be something to keep an eye on. Highs Monday should be in the 40s and to mid 50s. Ridging is forecast to build in for Tuesday with highs in the 50s. This warmth is short-lived as the next trough is already working east through the Rockies. Rain chances increase late Tuesday night into Wednesday with the trough and associated cold front. The track of the surface low is farther north into northern MN/southern Canada, thus the more organized rainfall appears to be tracking north of the local area. 09.00Z LREF probabilities are 45 to 60% for 0.10" or more. Ridging returns later Wednesday night through Friday with continued seasonably warm temperatures from the mid 40s to the mid 50s. Beyond Friday, there is some disagreement as to how the next trough over the West Coast deepens or if it will be less amplified moving into the Rockies sending some energy ahead of it with a warm front/precipitation developing Friday night into Saturday. At this time, the rainfall probabilities are 10 to 20% for 0.10" or more, so stay tuned. && .AVIATION /00Z TAFS THROUGH 00Z MONDAY/... Issued at 553 PM CST Sat Nov 9 2024 Rain showers continue to move through the region this evening with generally VFR visibilities. The heavier showers should end southwest to northeast over the next few hours with light drizzle and perhaps some patchy fog continuing overnight. Visibilities are expected to remain VFR overnight but may drop to MVFR at times in heavier precip/denser fog. Ceilings are expected to begin to drop to IFR conditions over the next few hours behind the showers with sites in central Iowa already reporting 500-900ft ceilings with some sites reporting 400ft ceilings. KRST would be the most likely to dip into LIFR conditions for ceilings as we head into the overnight hours, although probabilities of this are low (< 30%). Showers are expected to develop again Sunday morning with more restricted visibilities, generally around 2SM in the more robust showers. There is the potential for some rumbles of thunder with these showers, but confidence is on the low end so have left thunder out of the TAFs for now. Conditions will begin to improve Sunday afternoon. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ DISCUSSION...Naylor/Zapotocny AVIATION...Falkinham
Area Forecast Discussion
National Weather Service Billings MT
506 PM MST Sat Nov 9 2024 .KEY MESSAGES... - Mainly warmer and dry conditions for most areas through the weekend. - Weak disturbance brings rain/snow showers to the southern mountains and foothills Sunday. - Periods of increased winds over the western foothills tonight into next week. && .UPDATE... Quiet night upcoming as we are underneath flat ridging ahead of a Pacific shortwave along the coast. Upper low over NE continues to drift to the northeast, and any light precip that may have eked its way into the far southeast corner of MT has exited. HRRR is suggestive of a little fog in southeast Carter County tonight and this seems plausible given the 6pm observation of 40/34 at Alzada, and expectation of clearing w/ light winds tonight. Have tweaked pops/wx and winds, otherwise forecast is in good shape. JKL && .DISCUSSION... Today through Sunday night... Brief ridging continues over the region today, keeping conditions mild and dry. An upper level low over Nebraska is bringing precipitation right along the southeast MT border. Southeast parts of Carter county have a small chance of precip through this afternoon. Early morning Sunday, a weak pressure gradient sets up for a gap wind pattern at Livingston. Models have trended downward and the chance for hitting 50 mph is about 20%. Late Sunday morning, a weak disturbance will pass through the region, with the best chance for precipitation being snowfall for the Beartooth/Absaroka mountains (less than 2 inches likely). Lower elevations have a 10% chance or less at seeing any precipitation. High temperatures will be in the 50s to low 60s today, slightly cooling to the 50s Sunday. Low temperatures will be in the upper 20s to 30s Sunday and Monday mornings. TS Monday through Saturday... Warm and dry conditions are in the forecast for Monday. During this time, winds look to increase along the western foothills around Livingston, Nye, and Big Timber with gusts in the 30-45 mph range. As we get into Monday night, gap winds look to increase around Livingston to Nye ahead of a Pacific cold front passage. With this, the chance of seeing a 50 mph or greater gap wind gust remains around 60 percent. Once the front moves through Monday night into Tuesday morning, the gap wind threat will come to an end. Across the rest of the region, westerly winds will increase behind the front Tuesday with 20 to 40 mph wind gusts common over the plains of southeastern Montana. From Big Timber to Harlowton, winds may be a little stronger Tuesday with gusts to 50 mph possible (50-60 percent chance). Outside of winds, the chance of precipitation increases in the west Monday night as the next weather system approaches. At this time, the best chance of precipitation across the area comes Tuesday morning when there is a 20 to 90 percent chance of precipitation, highest over the mountains and lowest near Miles City and Baker. The chance of precipitation decreases Tuesday evening into early Wednesday morning as upper level ridging builds back in. With this system, the wave looks to remain open with little cold air. Therefore, precipitation amounts look to remain relatively light. Over the lower elevations, there is a high chance precipitation amounts remain below 0.20 inches. In the mountains, a couple inches of snow is likely, but the chance of seeing 6 or more inches of snow drops quickly outside of the highest peaks of the Beartooth/Absaroka Mountains (60 percent chance). Upper level ridging will bring warmer and dry conditions back to the forecast for most Wednesday into Friday. The low amplitude nature of the ridge may allow light snow showers to persist over the western mountains during this time though (15-30 percent chance). Another weather system is possible by next weekend, but uncertainty remains. Arends/RMS && .AVIATION... Winds over the western foothills (KLVM) will be breezy (25-40 mph)through the morning hours. VFR conditions will prevail. TS && .PRELIMINARY POINT TEMP/POPS... Sun Mon Tue Wed Thu Fri Sat ----------------------------------------------------------- BIL 038/057 032/060 040/051 031/054 037/059 031/050 029/040 01/E 10/B 14/W 00/U 00/U 11/B 33/W LVM 033/054 032/060 032/046 027/050 034/053 028/047 025/040 02/W 10/N 36/W 11/N 21/N 23/W 43/J HDN 030/058 030/061 036/051 028/055 031/060 028/052 027/042 01/B 10/B 16/W 10/U 00/B 12/W 33/W MLS 030/058 030/058 034/053 030/055 031/059 029/052 028/042 00/B 00/B 03/W 10/U 00/B 01/B 22/W 4BQ 030/059 032/059 036/052 031/054 033/060 030/053 030/043 00/U 00/U 05/W 10/U 00/B 01/B 22/W BHK 028/057 025/050 031/053 027/052 029/059 028/053 026/045 00/U 00/N 02/W 10/U 00/U 00/B 22/W SHR 029/060 027/062 033/052 024/054 029/061 027/052 025/042 00/U 10/U 07/W 20/U 00/B 01/B 34/W && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...None. WY...None. && $$ weather.gov/billings