Area Forecast Discussion
Issued by NWS Billings, MT
Issued by NWS Billings, MT
019 FXUS65 KBYZ 141852 AFDBYZ Area Forecast Discussion National Weather Service Billings MT 1252 PM MDT Fri Jun 14 2024 .DISCUSSION... Through Saturday Night... Satellite imagery shows a weak shortwave moving thru central MT and broad ridging over the high plains, downstream of a fairly deep low along the WA/BC coast. We had a bit more morning shower activity (w/ some embedded lightning) than previously thought, and it remains over southeast MT at 18z, but western areas are seeing clearing. Shortwave axis itself is just to our west so we are in a region of weak ascent for the afternoon and early evening. Livingston has warmed to 81F with a reasonably high dewpt of 51F. Just recently, cumulus developed over our western mountains including a small cell near Cooke City. So it appears our period of convection is commencing. Steep low level lapse rates support a risk of strong wind gusts w/ storms in our west and central parts, while the air mass in our east is more capable of producing severe hail along with wind (though wind is the greatest risk w/ all storms). Mesoanalysis shows pwats to about an inch along the Dakotas border w/ 850mb moisture advection continuing over our far east as of 18z. Bulk shear over much of our cwa is low (sub-25kts) but it is starting to rise in our far west and even near the Dakotas border (near 30kts). These trends will need to be watched. The 12z HREF showed a bit less shear than would be ideal (25-30kts) and overall less 40dbz coverage. Furthermore, models show less QPF in our east this evening, with a bit more mid level capping as 700mb temps are about +12C. All of that said, though convection should remain scattered and not well organized, there is a risk of localized strong winds and hail from now thru around 03z. For Billings, peak time for a thunderstorm looks like 2-5pm. Heights will begin to fall more earnestly tonight as the next Pacific shortwave moves inland. As a result, some showers will linger overnight in our west. Saturday is an interesting day as stronger energy lifts thru the northern Rockies in SW flow aloft. We will see some cooling and drying over our west, and even potential dry slotting from WY into our far S/SE, but a moist and unstable air mass with greater shear will linger over our NE/E as a cold front approaches from the west. Ingredients are favorable for possible severe storms in our east tomorrow, but especially in a region north/east of a line from Forsyth to Ekalaka. SPC updated Day2 outlook highlights this area (and much of northeast MT and western ND) for a slight risk of severe storms. Large hail and strong wind are risks. Otherwise, showers and weaker thunderstorms are expected with the fropa in our west. The front will bring a shift to gusty NW winds with 25-40 mph gusts expected. Any convection along the front could enhance wind gusts locally. Conditions turn drier Saturday night as the wave lifts north and we see post-frontal downslope winds. Saturday temps will reach the mid 70s west to lower 90s east. Saturday night will be cooler, signaling the start of a string of cooler days. JKL Sunday through Friday... Conditions early Sunday are expected to remain fairly dry before a weak shortwave moves in Sunday evening, bringing a 20-30% chance of light showers to the plains and a 30-50% chance to the mountains and foothills through early Monday. Then, the pattern for next week will become more unsettled, with a trough dropping into the region Monday. Coupled with PWATs approaching 0.75-1 inch at times, bands of heavier precipitation are expected, although the exact placement of the tracks is still uncertain. Currently, for Monday through Wednesday, the greatest accumulations are expected mostly north and west of I-94, with a 50-60% chance of seeing greater than half an inch. Late Monday into early Tuesday morning, snow levels are expected to drop to around 7000 ft. The total snow amount possible will depend on where the bands of precipitation set up. Currently, there is a 40% chance of at least 6 inches of snow over the highest peaks. For late Wednesday through Friday, models agree on conditions remaining unsettled, although there is disagreement on the timing and strength of the next systems. High temperatures will drop 10-20 degrees from Saturday, with highs in the mid 60s to mid 70s Sunday. Temperatures will continue to cool through Tuesday, with highs falling into the upper 50s to low 60s. Then, temperatures are expected to gradually warm through the end of the week, with highs in the 70s to near 80 by Friday. Archer && .AVIATION... Scattered showers and thunderstorms will impact the region thru around 05z this evening. A few storms could produce strong/erratic wind gusts and mostly small hail, along with brief heavy rain and reductions to MVFR/IFR. Confidence in a thunderstorm impacting a TAF site is relatively low at this time, while erratic winds will be more widespread. The potential for light showers will linger overnight into Saturday morning. Thunderstorms are possible again tomorrow afternoon. Otherwise, VFR will prevail over the next 24 hours. TS POTENTIAL TIMES TODAY: BIL: 19-03Z LVM: 19-01Z MLS: 00-05Z SHR: 18-02Z JKL && .PRELIMINARY POINT TEMP/POPS... Sat Sun Mon Tue Wed Thu Fri ----------------------------------------------------------- BIL 058/086 050/072 049/065 045/061 043/072 049/075 054/079 32/T 10/B 26/T 73/T 12/W 22/T 23/T LVM 052/077 039/068 042/062 038/058 036/067 042/072 047/077 35/T 10/B 38/T 75/T 12/T 23/T 23/T HDN 056/090 048/074 049/070 045/062 042/073 048/077 054/081 42/T 20/B 36/T 73/W 11/B 22/T 33/T MLS 061/090 051/072 051/065 047/061 042/070 049/075 055/079 43/T 50/U 35/W 84/W 11/B 32/T 33/T 4BQ 060/092 052/073 053/067 048/064 044/070 050/076 055/079 52/T 20/B 54/T 72/W 12/T 32/T 33/T BHK 058/090 050/072 047/066 046/063 041/069 048/075 053/078 42/T 50/U 44/T 84/W 12/W 32/T 43/T SHR 055/090 045/073 045/072 042/061 039/071 046/075 052/079 31/U 10/B 45/T 62/W 22/T 22/T 32/T && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...None. WY...None. && $$ weather.gov/billings