textproduct: Glasgow

KEY MESSAGES

- Mild and dry weather continue today.

- Look for chances for rain tonight and Wednesday with a chance of a wintry mix Wednesday night and a chance of light snow Thursday.

- Gusty west to NW winds are expected on Wednesday with much colder temperatures Wednesday night and Thursday.

DISCUSSION

WEATHER PATTERN OVERVIEW:

Zonal upper flow sets the stage for a weak surface low pressure system to enter the region late this afternoon with embedded shortwaves through the end of the week. Look for rain chances to start this evening with a warm front and continue overnight. Forecast temperatures have warmed enough tonight that the precipitation is expected to be all rain.

The rain chances move to the east early Wednesday morning. A cold front Wednesday afternoon will bring another chance for rain. Gusty west to NW winds are also expected Wednesday afternoon and evening. With the ice gone from Fort Peck Lake, the first Lake Wind Advisory is likely Wednesday afternoon and evening for Fort Peck Lake.

Given warm temperatures and windy conditions on Wednesday there has been thought on elevated fire conditions. Wind gusts will likely exceed the relative humidity at times in some areas during the afternoon in the presence of dry fuels. However, given the presence of cloud cover and light precipitation chances, confidence is low on widespread fire concerns. More importantly will be the tightening pressure gradient as the surface low and cold front drift southward. This will bring west to NW winds ranging from 20 to 30 mph, gusting to 40 mph or better along and north of the Missouri River. The NBM has 50 to 100 percent probabilities for wind gusts exceeding 40 mph north of the Missouri River on Wednesday afternoon with 10-50 percent probabilities to the south. HREF probabilities of 40 mph gusts are lower than the NBM with 30-60 percent chance north and less than 10 percent south. Meanwhile, probabilities remain very low for gusts in excess of 55 mph for now, except for Phillips and Sheridan Counties where NBM probabilities are around 30 percent but near zero probability in the HREF. Will hold off on any High Wind highlights for now.

Look for much colder temperatures for Wednesday night and Thursday with chances for light snow. In fact, lows in the morning will be in the teens near the Canadian border. It would not be surprising to see isolated single digit temperatures. Thursday highs will range from the upper 20s to the lower 40s. This cold spell will be short lived however with ensembles showing upper ridging and milder temperatures to return starting on Friday and continuing through the weekend.

FORECAST CONFIDENCE & DEVIATIONS:

Used a blend of NBM and NBM90 for winds on Wednesday given the tightening pressure gradient expected over the region. The NBM captured the forecast well otherwise. Confidence is high on light precipitation chances through Thursday with windy conditions on Wednesday. Lower confidence however exists on the exact timing, location, and amount of precipitation. There are also some precipitation type challenges to work out Wednesday night and Thursday.

AVIATION

LAST UPDATE: Tuesday March 24 at 0800Z

FLIGHT CATEGORY: VFR

DISCUSSION: There will be varying amounts of mid and high level clouds today. A mix of low and mid level clouds are expected tonight with chances for light rain at times as a warm front moves through the area.

WIND: East to SE winds 5 to 15 knots this morning will veer to the south around 18z (noon MDT) and to the west this afternoon. Winds will be light and variable this evening.

GGW WATCHES/WARNINGS/ADVISORIES

None.