Marine Weather and Tide Forecast for Silver Gate, MT

DISCUSSION

Through next Wednesday...

Satellite imagery shows an approaching Pacific trof over WA/OR and a downstream ridge axis over eastern MT, and heights are beginning to fall over our forecast area. A surface cold front is located from far western MT to southwest ID as of 17z, and mesoanalysis shows a region of healthy pressure falls from near Butte to Salmon. As a result, we are seeing easterly winds and not quite ready to mix the SW flow aloft. Weak convection has developed in central ID but our west is still capped. Overall, we are still a few hours from seeing the risk of t-storms reach us. Expect that to be ~21z. SPC has expanded the slight risk for severe t-storms to include areas from Red Lodge to Lavina westward, and a marginal risk extends eastward to Miles City & Broadus. This morning's HRRR shows best probs for convective high winds from Billings westward and northward, as far east as northern Rosebud.
Obviously, the risk of strong/erratic winds will exist with any weak t-storm or shower, as the boundary layer will be deeply mixed and dry. No chance of anything but tiny hail today.

Following the convective wind potential (there may be multiple rounds until the front arrives from the west this evening) we transition to synoptically-driven/strong/post-frontal west winds.
Subsidence arrives in our far west by 06z and is over most of our cwa by 12z. Confidence is high for windy conditions across the area through tomorrow, but there remains uncertainty with magnitude of highest gusts. GFS continues to be strongest with mid level winds and the EC weaker, and historically some sort of blend of the two verifies best. The 12z GFS has actually trended a bit weaker so there is some confidence there. Existing wind highlights look good and will make no changes, and will also make no further additions in coverage. With the greatest 850-700mb winds occurring before 18z tomorrow, do not see a need to expand east of Yellowstone/Musselshell as there shouldn't be enough mixed wind during peak heating hours, but this will need to be monitored. The immediate wind risk is with convection between 21-04z. Heads up if you have outdoor plans this evening.

Regarding fire weather, much of the region has greened up sufficiently to prevent a significant risk of grass fires, but there are patches that are drier, and larger fuels are reporting below normal fuel moistures. Please take care to not spark a fire with the dry and windy conditions through tomorrow! In fact, it will remain breezy (though not as strong and a bit cooler)
Friday. T-storms this evening will produce only spotty light rainfall.

Look for temps in the mid 60s to mid 70s tomorrow through Saturday, with much less wind and higher humidities by the weekend.

Things get more interesting this weekend as a stronger trof w/ much lower heights drops through the northern Rockies. This will bring cooler temps and increasing precip chances, with high confidence, but details remain highly uncertain. An open trof will mean lower precip totals while a closed low developing over WY would result in heavier upslope precipitation. Either way, temps aloft will be cold enough such that mountains will see snowfall.
If a more dynamic system materializes we could also be looking at wet snow for the foothills. Look for temps somewhere between the mid 40s and near 60F Sunday & Monday (warmest east). Consensus is for temps back to the 60s Tuesday & Wednesday, but there is potential for another trof to arrive by then. Generally speaking, the weather pattern is looking active and cooler through the first half of next week.

An interesting side note. When the Billings airport reaches 90F today, it will have seen 50F in Jan, 60F in Feb, 70F in Mar, 80F in Apr and 90F in May. While these temps are not uncommon in any of these months, it occurring in all 5 months has happened only 4 other times since 1934, most recently in 1992.

JKL

AVIATION

03Z UPDATE...

Dry thunderstorms have tapered off this evening and high winds will pick up midnight through mid day Thursday. Widespread gusts to 40kts are possible with higher gusts for KLVM/K6S0/K3HT where there is a 40% chance for gusts to 60 kts through the morning. TS

PRELIMINARY POINT TEMP/POPS

Thu Fri Sat Sun Mon Tue Wed ----------------------------------------------------------- BIL 052/075 047/072 041/071 041/050 036/051 035/063 042/064 20/N 00/N 00/B 55/W 54/W 21/B 23/T LVM 042/070 040/068 036/065 032/042 028/047 029/058 035/062 30/N 00/N 03/T 88/T 75/T 22/T 23/T HDN 052/075 045/073 038/073 041/053 035/051 033/063 039/064 20/N 00/N 00/B 35/W 65/W 21/B 23/T MLS 052/074 046/072 039/073 044/057 036/050 034/061 040/064 50/N 00/N 00/B 44/W 55/W 31/B 22/W 4BQ 052/073 042/072 038/074 045/056 036/047 033/059 039/062 40/N 00/U 00/B 33/W 66/W 21/B 12/W BHK 050/073 043/071 036/072 043/058 034/046 031/058 037/062 20/N 00/N 00/B 45/W 66/W 32/W 12/W SHR 045/075 039/072 035/072 037/049 030/045 028/058 034/061 20/N 00/U 00/B 38/T 87/T 22/T 13/T

BYZ WATCHES/WARNINGS/ADVISORIES
MT...High Wind Warning in effect until 9 PM MDT Thursday FOR ZONES 29-34-42-63-141-172-228-235.
Severe Thunderstorm Watch 201 in effect until 11 PM MDT this evening FOR ZONES 29>31-56>58-67-138-139-169>171-173-235.
High Wind Warning in effect until 6 AM MDT Thursday FOR ZONES 56-139-170.
High Wind Warning in effect until 10 PM MDT this evening FOR ZONE 64.
Wind Advisory in effect until 9 PM MDT Thursday FOR ZONES 65-66.
High Wind Warning in effect until 6 PM MDT Thursday FOR ZONE 68.
WY...None.