Area Forecast Discussion
Issued by NWS Billings, MT
Issued by NWS Billings, MT
793 FXUS65 KBYZ 210219 AFDBYZ Area Forecast Discussion National Weather Service Billings MT 819 PM MDT Sat Jul 20 2024 .UPDATE... Afternoon convection has dissipated quickly this evening, and as of 8pm is really confined to areas near the Pryor and Bighorn Mountains. This is consistent w/ the latest mesoanalysis showing PV max moving from south central MT to northern WY. There are a few showers north of our cwa, but they are also tapering off and feel that as we transition to subsidence and darkness we should be dry from ~10pm thru the remainder of the night. Regarding smoke, there is plenty of it lofted and that will remain the case for the foreseeable future. Surface visibilities remain 10SM or greater regionwide. The northerly flow will continue advect Canadian smoke southward (there are several active fires in northern AB and BC), and we could begin to see surface smoke become more of an issue tomorrow. This is what the HRRR is suggesting and will need to monitor. JKL && .DISCUSSION... Rest of Today through Sunday Night... Isolated to scattered showers and thunderstorms will progress south/southeast through the afternoon and evening today. With minimal shear and only modest instability in place, any storm that initiates looks to remain garden variety, short lived, and relatively slow in motion. With that said, the main threats are heavy rain and wind gusts up to 40 mph. Small hail is also possible under the strongest storms. Activity will decrease late this evening through Sunday morning before isolated showers and thunderstorms are expected to form again Sunday afternoon and evening, mainly over the mountains and east of Billings. Again, minimal shear and instability will keep things weaker, with gusty winds up to 40 mph and heavy rain being the main threats. Outside of this activity, smoke concentrations look to increase aloft over the next 24 hours. Eastern Montana will see the push by this evening, with the rest of the area getting into it by Sunday afternoon. While the majority of the smoke looks to remain aloft, some is expected to mix down to the surface. If you have special sensitivities to smoke, make sure to check your local air quality before headings outside tomorrow. High temperatures Sunday are in the upper 80s to lower 90s across the area. Expect overnight lows to be in the 50s and 60s tonight and Sunday night. Arends Monday through Friday... Ensembles remain in good agreement with the overall pattern through the middle of the week, with a bit more uncertainty from Friday and beyond. Upper ridge axis centered over western Montana will slowly shift east through Wednesday, settling over eastern Montana. Gradually warming temperatures can be expected, with highs in the upper 80s to lower 90s Monday, increasing into the 90s for Tuesday, and middle 90s to lower 100s for Wednesday. NBM probabilities for temperatures of 100 degrees or higher are 50% or greater for the river valleys mainly from Billings east. Isolated to scattered showers and thunderstorms (15-30% chance) are possible over the mountains during the afternoons and evenings, with less coverage out onto the lower elevations. Thursday will be another hot day ahead of a ridge breakdown with high temperatures mainly in the upper 90s to lower 100s. A limiting factor on the temperatures could be smoke aloft. A cold front is currently progged to enter the west during the late afternoon, moving east through Thursday evening. Isolated to scattered showers and thunderstorms (20-50% chance, greatest over the southwest mountains) are possible with the cold front. Will need to keep an eye on Thursday, as this is a pattern that brings fire weather concerns. Cooler conditions and additional chances for showers and thunderstorms (20-50%, greatest over the west) are progged for Friday as a weak shortwave lifts through the region. Highs in the upper 80s to 90s are currently forecast. STP && .AVIATION... Isolated showers and thunderstorms, mainly south of KBIL at 02Z, will dissipate entirely by 04Z this evening. Isolated thunderstorms are expected Sunday afternoon as well, mainly east and south of KBIL. VFR will prevail over the next 24 hours. Lofted smoke will continue reduce slant range visibility across the region. Surface impacts from smoke are less certain, but surface visibilities may decrease some by Sunday. JKL && .PRELIMINARY POINT TEMP/POPS... Sun Mon Tue Wed Thu Fri Sat ----------------------------------------------------------- BIL 062/092 063/093 063/097 066/103 068/103 067/094 062/089 11/H 00/U 00/U 00/G 02/T 22/T 22/W LVM 054/090 053/092 055/097 058/100 061/098 057/091 054/087 01/H 00/U 01/U 11/U 13/T 34/T 33/T HDN 058/093 060/094 060/098 062/105 065/104 064/096 059/090 22/T 00/U 00/U 00/G 01/G 22/T 32/W MLS 063/091 063/091 065/095 066/102 069/103 070/094 065/089 22/T 01/U 00/U 00/G 00/G 21/B 31/B 4BQ 061/090 061/090 062/094 065/101 067/104 070/096 065/090 12/T 01/U 00/U 00/G 00/G 10/B 21/B BHK 059/089 059/089 060/093 063/098 064/101 066/096 063/092 12/T 01/U 00/U 00/U 00/G 11/B 22/T SHR 055/090 055/090 056/094 058/100 061/102 062/094 058/089 22/T 01/U 00/U 00/U 01/G 22/T 23/T && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...None. WY...None. && $$ weather.gov/billings