textproduct: Great Falls

KEY MESSAGES

- Impactful rainfall is now over with, but it will take about 6 to 12 hours for the water to recede in flooded areas.

- Temperatures warm back up to seasonal normals, with daily chances for thunderstorms through Friday.

- Potential breezy conditions on the 4th of July over North Central MT.

DISCUSSION

- Meteorological Overview: The upper level low that has caused all the rain/snow over the CWA the past 3 days is now exiting the area this morning. Rainfall has decreased significantly overnight, with just a few scattered showers remaining early this morning.

For the rest of today, expect a quick return to near normal temperatures, but also for a few scattered showers/thunderstorms this afternoon.

For Wed thru Fri...expect daily chances of afternoon/evening showers/thunderstorms as upper level disturbances move from southwest to northeast through the CWA. At this point I am not expecting widespread severe thunderstorms, but with the afternoon instability, an isolated severe storm can not be ruled out.

For the 4th of July into early next week...afternoon temperatures will start to go above normal during this period. The chances for thunderstorms will be quite low most days as well. It could be a bit breezy on Saturday over North Central MT, otherwise generally lighter winds are expected next week.

- Forecast Confidence & Scenarios:

Thunderstorms -> the main concern over the next few days will be the potential for an isolated severe thunderstorm. With afternoon heating and the recent moisture, and isolated severe storm can not be ruled out, however the probability is generally less than 5 percent at this time for most days.

Winds -> A short period of stronger winds could develop on Saturday over North Central MT. Overall winds will not be to strong, generally in the 30 to 40 mph range, but this could have some impacts to 4th of July fireworks activity.

Warmer temperatures next week -> Some forecast models are forecasting afternoon temperatures about 10 degrees warmer than currently forecast for next week. Overall we will continue to monitor this potential for warmer afternoon temperatures. Brusda

AVIATION

30/12Z TAF Period

A few light showers will affect the CWA this morning, but scattered showers/thunderstorms are once again possible this afternooon and evening. However, coverage of precipitation will be much smaller of an area than it has been over the past 3 days. Mountains/passes could be obscured a bit this morning and again this afternoon by clouds/precip. Brusda

HYDROLOGY

A Flood Warning is in effect for a good portion of western Glacier County into this afternoon. Overall the heavy precipitation has ended, with just some scattered showers/thunderstorms expected over the next few days.

That being said, it will take another 6 to 12 hours for the water to recede below flood stage for most areas, thus the flood warnings continue until further notice. Brusda

PRELIMINARY POINT TEMPS/POPS

GTF 74 51 75 50 / 20 20 40 10 CTB 70 48 72 47 / 30 10 0 10 HLN 72 51 72 49 / 40 60 70 50 BZN 70 44 73 45 / 30 30 60 40 WYS 61 33 68 36 / 30 10 20 20 DLN 67 43 70 43 / 50 60 70 30 HVR 75 51 78 52 / 60 10 10 20 LWT 70 45 72 46 / 10 10 60 50

TFX WATCHES/WARNINGS/ADVISORIES

None.