525 FXUS65 KBYZ 051603 AFDBYZ Area Forecast Discussion...Updated National Weather Service Billings MT 1003 AM MDT Fri Apr 5 2019 .UPDATE... Some weak echos continue across mainly Rosebud County, but still does not look like anything is reaching the ground. Still expecting more showers to develop this afternoon mainly from Billings west. There is still some instability across the area, so an isolated rumble of thunder is still possible. No changes to the forecast. Reimer && .SHORT TERM...valid for Tdy and Sat... A few light showers were moving across the area early this morning on radar. These showers should be out of the area by 12Z. An upper trough will approach the area from the WSW today through this evening. The trough will spread showers into western and central parts of the area today, and then precipitation will shift N out of the area this evening around low pressure over S central and SE MT. The HREF showed updraft helicity over the W and central areas with steep lapse rates, so have included a slight chance of thunder this afternoon and evening. The forecast area will be mainly dry late tonight. Northern portion of the trough will affect the area Saturday and Sat. night, bringing a cold front through the region on Saturday. Chances for showers will overspread the entire area during Saturday, and then shift E out of the area Sat. night. There were decent CAPE values over SE MT Sat. afternoon, so included a slight chance of thunder there through the evening. The SW mountains will receive snow that will be aided by SW upslope flow. Expect no more than 1 to 3 inches each period. Highs will be in the 50s and 60s each day, with today being the warmer of the two days. Arthur .LONG TERM...valid for Sun...Mon...Tue...Wed...Thu... Sunday is still shaping up to be warm, dry, and breezy day. Westerly flow in the mid levels is progged to mix down in the afternoon with 15 to 30 mph winds likely. This raises concern for fire danger. Temperatures look to be 10 to 15 degrees above normal from Billings eastward and we have had reports of some burns getting out of control recently. Only fly in the ointment is cloud cover. Current cross sections and other model data suggest mostly cloudy in the west, but possibly thin to partly cloudy skies in central/east which may allow deep enough mixing to be a problem. Will issue a Rangeland Fire Danger for Sunday (11 am to 8 pm) for the central zones. Combination of above normal temperatures, breezy conditions and humidity dropping into the upper teens and 20s will increase the rangeland fire threat as fuels have not had chance to green up yet. For the rest of the the extended the trend continues to be towards cooler and wetter. By Tuesday evening a fairly strong trough will start moving into our CWA bringing a better chance of precip. Model spreads are decreasing a bit so will continue to advertise trend in the direction of the cooler/wetter ensemble means. BT && .AVIATION... VFR will prevail under a mid and high level cloud deck. Isolated rain/snow showers will be mostly confined to the mountains with some obscurations this morning. Showers and isolated thunderstorms and high elevation snow will increase in the west/southwest after 20Z and move northeast across the region. MVFR is possible within the showers and thunderstorms. BT/RMS && .PRELIMINARY POINT TEMP/POPS... Tdy Sat Sun Mon Tue Wed Thu ------------------------------------------------------- BIL 068 043/064 040/068 044/063 042/056 038/051 034/050 1/E 23/W 20/B 23/W 45/W 54/W 33/W LVM 055 035/052 033/055 037/052 032/046 029/043 024/043 5/T 43/W 11/N 46/W 45/W 44/W 32/W HDN 068 040/064 037/068 042/063 039/056 035/051 030/050 0/B 14/W 30/B 23/W 45/W 55/W 33/W MLS 068 042/065 040/067 043/062 040/057 037/051 031/050 0/B 12/T 30/U 12/W 24/W 43/W 22/W 4BQ 068 041/065 038/066 041/063 040/057 037/048 031/048 0/B 14/T 40/U 11/B 24/W 55/W 33/W BHK 065 042/061 039/063 041/060 038/054 034/046 028/047 0/B 23/T 30/U 11/N 23/W 43/W 22/W SHR 065 037/060 034/065 038/063 038/054 033/046 028/046 1/B 05/W 40/U 12/W 35/W 65/W 44/W && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...None. WY...None. && $$ weather.gov/billings