textproduct: Glasgow

KEY MESSAGES

- Showers and thunderstorms are expected in the southern part of the area through the early overnight. Some storms may be severe in the far southeast.

- A slow warm up is expected Tuesday through Friday. There is a chance of showers and storms in the east and northeast Tuesday and Wednesday.

- Another system will arrive on Thursday evening to bring areawide rain showers and storms. An ample amount of rain is expected through the weekend.

DISCUSSION

WEATHER PATTERN OVERVIEW: A low pressure system will slowly dance its way through the area from now through late tonight before it moves east in the morning. This system is creating some rain showers over the south, but daytime heating will allow some instability to occur in the atmosphere, so thunderstorms are expected with this activity. One or two cells in the southeast have potential to become severe from 5 PM to 9 PM. Hail and wind are the main threats. Showers and storms are expected to end by around 3 AM tonight as the low pressure system exits.

The GFS ensemble is suggesting this trough will linger in western North Dakota tomorrow and Wednesday, so there is a decent chance of rain showers and weak thunderstorms occurring in the east from about noon to 8 PM Tuesday, and in the northeast from noon to 6 PM Wednesday. High temperatures are expected to reach their peak on Thursday as the ridge builds in, but an upper trough is expected to strengthen by the afternoon, so an active pattern will be the story from Thursday evening onward. Although it is a bit early to put amounts on the table, there is a decent chance of rainfall totals being over half an inch for most locations over the weekend.

FORECAST CONFIDENCE & DEVIATIONS: Only deviation was to increase PoPs in the east on Tuesday afternoon.

There is moderate to high confidence in thunderstorms occurring in the south, with low to moderate confidence on severe weather occurring in the far southeast this evening.

There is moderate confidence on rain showers and thunderstorms occurring in the east tomorrow afternoon and in the northeast on Wednesday afternoon.

There is high confidence in rain showers and thunderstorms occurring this weekend. Confidence is the same in accumulations exceeding half an inch of rain from Thursday night through Monday.

AVIATION

LAST UPDATE: 1820Z

FLIGHT CAT RANGE: VFR - MVFR

DISCUSSION: A low pressure system is slowly moving through the area today, and much of this activity is in the south. As this progresses east, the showers are expected to run into some instability. There is a low chance of severe thunderstorms occurring for KGDV and KSDY, so there is low to moderate (30 to 50 percent) confidence of MVFR conditions occurring between 23Z Monday and 03Z Tuesday with these storms. As the trough slowly pushes into North Dakota by the morning, low clouds may move in. There is moderate confidence of MVFR ceilings occurring from 12Z to 18Z Tuesday. Then VFR as a weak ridge moves in.

WIND: North northwest at 7 to 14 knots, becoming light and variable after 02Z, becoming northwest at 10 to 20 knots after 12Z Tuesday.

GGW WATCHES/WARNINGS/ADVISORIES

None.