textproduct: Great Falls

KEY MESSAGES

- Gusty winds persist along the Rocky Mountain Front with breezy conditions along the plains through the week.

- Mostly dry conditions through the week, with a few periods of light mountain snow.

- A warmup in temperatures continue this week, reaching well above normal by mid week.

DISCUSSION

- Meteorological Overview:

This weakening upper level shortwave passing through through Tuesday morning will continue to bring light mountain snow with some snow flurries coming off the mountains to the lower elevations. Current radar shows light reflectivity along the stationary boundary draped across Cut Bank through Lewistown. Dry air at the surface is making precipitation struggle to the surface. If it does make it to the surface, it will be snow flurries. Snow will generally be a dusting if any accumulates across the higher terrain. Upper level ridging builds in briefly again for the rest of the day Tuesday. This will allow for clouds to clear throughout the day, with mild afternoon temperatures (except for the northern Hi-line, where weak mixing will keep cooler temperatures for another day).

Wednesday, an approaching shortwave trough coming from the Pacific coast will stream in a small amount of moisture to the Continental Divide. This will bring some light mountain snow, but it's not looking likely appreciable precipitation moves off of the mountains into the lower elevations.

It will remain breezy/gusty across the Rocky Mountain Front and North-Central MT plains with a mid level jet and pressure gradient from these passing waves. Friday/Saturday looks to be the windiest time from of the week with better lee troughing/pressure gradient setting up. However, ensemble guidance and the EFI's aren't hinting at high wind criteria at this time. Currently, 60-80% probabilities for 58 mph wind gusts stay towards the immediate foothills of the Rocky Mountain Front.

The ridging/chinook winds will help attribute to the warming trend this week, with temperatures reaching well above normal by mid week. The passing waves should help limit the warm up, but temperatures regardless will warm up by 10-20 degrees late week. With temperatures warming up, we will have to watch for ice jams as the rivers thaw throughout the week.

In terms of precipitation, the current stationary front will slide east throughout the week, which will keep most chances for lower elevation precipitation off in eastern MT. With the wave bringing in westerly flow, there will be light mountain snow at times through the weekend, with lower elevations looking to get mostly downsloped. -Wilson

AVIATION

27/06Z TAF Period

A shortwave embedded within a northwesterly flow aloft will maintain abundant, mostly mid- and higher level, cloudiness through Tuesday morning. While VFR conditions will generally prevail, expect mountain obscuration to persist through at least 27/15Z, particularly over and near the central island ranges and the mountainous terrain of Madison/Gallatin counties. - RCG

PRELIMINARY POINT TEMPS/POPS

GTF 37 29 44 26 / 10 20 0 0 CTB 36 24 41 21 / 0 10 0 0 HLN 25 23 42 21 / 10 20 10 0 BZN 32 20 40 16 / 0 10 10 0 WYS 25 1 29 1 / 0 0 0 0 DLN 39 20 40 19 / 0 0 0 0 HVR 29 11 27 11 / 0 20 10 0 LWT 30 21 40 21 / 0 10 0 0

TFX WATCHES/WARNINGS/ADVISORIES

None.