Marine Weather and Tide Forecast for Big Timber, MT

UPDATE

Low clouds and patchy fog have formed over portions of the area this morning, most widespread over the lower Yellowstone River Valley east of Forsyth. The low clouds/fog will bring local reductions in visibility into the morning hours, before burning off. Showers are starting to show up on radar over southern areas, and expect the showers to move north and east through the morning hours, becoming more widespread as a disturbance lifts into the region. The area remains on track to see showers and thunderstorms today into this evening, with strong storms possible over far SE MT. The SPC has a marginal risk for severe thunderstorms for far SE MT. Storms will be capable of strong gusty winds, heavy rainfall and small hail. Stay weather aware if you have outdoor plans. STP

DISCUSSION

Today through Sunday...

The region remains under southwest flow as a low currently over Idaho is expected to push up a disturbance through the area today.
Showers are expected to begin this morning over south central MT and move northeast through the morning reaching southeast MT by late morning to early afternoon. The HRRR and individual hi-res models have trended up on the instability with MUCAPE values of around 500-750 J/kg and around 30 kts of 0-6 km shear. This will allow for a better environment for thunderstorms than we have seen the past couple days. Forcing and moisture will also be plentiful as the surface low moves over southeast MT and precipitable water values near three quarters of an inch. With this, the concern for heavy rain does arise with any stronger thunderstorms and wherever the low sets up as models are putting out slow storm motion. There is still some uncertainty within individual models on where this will set up, but the general area looks to be in the east central MT vicinity. Outside of the heavy rain threat, small hail and gusty winds 40-50 mph are possible. Currently, there is about a 40% chance for a stronger storm to produce wind gusts to 60 mph. Additionally, a weak pressure gradient over the western foothills will keep breezy west/southwest wind gusts of 30-45 mph today for areas of Livingston to Big Timber.

As a more westerly flow builds in for Tuesday, precip chances are minimal (small chances over higher terrain). As a low pressure system moves in from the west late Wednesday, precipitation chances increase (50-80%). There is still some uncertainty on the exact track of this system as ensembles have energy splitting over our region or staying together. This would impact precip placement and totals. Into Thursday evening a push of cooler air moves through, bringing moderate chances for snow across the lower elevations. Currently, there is about a 50-80% chance for at least a quarter inch of precipitation for south central MT/northern WY and 20-40% chance for southeast MT late Wednesday through Friday morning. The Beartooth and Crazy mountains have about a 40-60% chance for at least an inch of liquid precip with about a 50% chance for about a half an inch for the Bighorns/Pryors. The Beartooth/Absarokas have about a 50-70% chance for at least a foot of snow, with a 20-30% chance in the Crazies and Bighorns.

Higher heights looks to build in for the weekend, creating warmer and drier conditions. High temperatures for the week look to remain in the 50s and 60s through Wednesday, dropping to the upper 30s and 40s by Friday. Temperatures rebound into the 50s and 60s by the weekend. TS

AVIATION

VFR will prevail into the morning for most areas, with stratus and patchy fog over the east bringing areas of MVFR to IFR conditions from KMLS to KBHK down through K97M through roughly 16z. Patchy fog creating localized vsby reductions will burn off elsewhere through the morning hours.

Look for southwest to west winds to increase over the western foothills (KLVM, K6S0, and K3HT) this morning. Another round of isolated to scattered showers will move into the area today. Over far eastern Montana (around KMLS, KBHK, and K97M), isolated to scattered thunderstorms are forecast during the afternoon and evening as well, with the potential for a few stronger storms with gusty and erratic winds of 40-60 kts, heavy rainfall and small hail being the main threat. Local MVFR conditions are possible with the convection. STP

PRELIMINARY POINT TEMP/POPS

Tdy Tue Wed Thu Fri Sat Sun ------------------------------------------------------- BIL 062 041/066 042/067 039/046 026/047 028/058 035/068 3/W 21/U 01/E 59/W 53/J 11/U 01/B LVM 057 033/060 038/059 032/040 021/043 023/054 032/063 4/W 31/N 05/W 99/W 53/J 11/U 01/B HDN 062 039/067 037/070 037/050 025/047 024/059 032/070 5/W 21/B 11/B 49/W 64/J 21/U 11/U MLS 061 041/066 040/069 040/052 024/042 022/054 032/067 7/T 50/U 00/B 35/W 42/J 11/U 00/U 4BQ 062 038/064 039/070 042/058 024/041 023/052 030/067 4/T 11/U 00/U 14/W 63/J 11/U 00/U BHK 059 036/064 037/069 039/058 022/037 019/049 027/062 7/T 41/B 00/U 12/W 52/J 11/U 00/B SHR 059 032/061 033/066 037/051 021/041 020/052 027/065 5/W 12/W 00/B 29/T 86/J 21/U 11/U

BYZ WATCHES/WARNINGS/ADVISORIES
MT...None.
WY...None.