571
FXUS65 KGGW 250833
AFDGGW

Area Forecast Discussion
National Weather Service Glasgow MT
233 AM MDT Sat May 25 2024

.DISCUSSION...

KEY MESSAGES:

1) Scattered showers and general thunderstorms will start in the
west late this afternoon and move across northeast montana slowly
overnight.

2) Expect a slow warming trend into Wednesday with widespread 80s
Tuesday and Wednesday.

3) Any fog early this morning over the Missouri and Milk River
valleys or north of them will likely clear out before or around
9AM.


WEATHER PATTERN OVERVIEW:

With dewpoint depressions near 1 to 2 degrees across the region
and rain falling just before or after sundown and night time
clearing of skies. Fog will be possible this morning with
greatest chance being over the Missouri River Valley and areas
north of the missouri and Milk river valleys being most impacted.
This fog should clear around 7 to 9 AM.

Unsettled pattern will hold with two distinct periods for
prolonged showers and thunderstorms. One is this afternoon to
Sunday evening, while the other is Wednesday afternoon to Thursday
evening. Rain totals appear to vary from a couple hundredths to
upwards of a quarter of an inch with a tenth of an inch being the
most common output for the first event. The second event is more
in flux with synoptic features not quite settling into place yet
and therefore a good determination on rain totals can not yet be
derived. A ridge will build into the area between these two rain
events allowing highs to reach the widespread 80s by Tuesday and
Wednesday.

CONFIDENCE & DEVIATIONS:
Confidence in morning fog seems shaky as model output across the
board is failing to place any fog along the Missouri and Milk
River Valleys in well known locations like Wolf Point(KOLF) and
Poplar(KPO1). Currently having to go off script and hand enter
data into the hourlies through about sunup.

Confidence holds fairly strong through about Wednesday when the
second shortwave arrives and ensemble consistency begins to break
apart. Surface wind fields at this time are in flux along with
rainfall total grouping being wider over the ensembles. A surface
low pressure system may or may not form with the disturbance`s
passage with about half the ensembles producing it.
GAH/TFJ


&&

.AVIATION...

LAST UPDATED: 0830Z

FLIGHT CAT: VFR-VLIFR.

DISCUSSION: Patchy fog is possible in some locations this
morning with mainly KOLF and perhaps KSDY being impacted. Most
fog will begin clearing around 13Z and gone by roughly 15Z.

A new round of rain showers and isolated thunderstorms is
expected to begin impacting the terminals around 22Z and last into
the nighttime hours. These showers may not fully clear from
northeast Montana until about Sunday evening.

SFC WIND: Light and variable this morning through the rest of
today and becoming east this evening.

GAH


&&

.GGW WATCHES/WARNINGS/ADVISORIES...
None.


&&

$$

weather.gov/glasgow