textproduct: Glasgow

KEY MESSAGES

- Dangerous heat is being reduced to Prairie and Wibaux counties Tuesday with an uptick Wednesday. Extended the Heat Warning through Wednesday night for those two counties and trimmed the Advisory as well. daniels and Sheridan counties are the only ones that fell out with no Heat headlines after tonight. - Temperatures will reduce to 80s and 90s for highs through the work week.

- There is the possibility of severe thunderstorms moving northeast into the NW zones Tuesday evening. High humidity may also give rise to flooding concerns.

DISCUSSION

WEATHER PATTERN OVERVIEW: Closed upper high will linger over the northern high plains the first part of this week, keeping the heat going over the Dakotas and into our SE zones through Wednesday. Heat Warnings were trimmed for tomorrow to just Prairie and Wibaux counties. Daniels and Sheridan counties drop out of the Advisory tomorrow with an advisory for the remainder of the zones.

Then an upper disturbance sends storms northeast into the CWA about 03z. Updraft helicity and Max Updraft from the HREF is showing severe thundertorm potential for the western zones. With the high Precip Waters (1.0 to 1.8"), flooding could also be a concern. Will go ahead and issue a Flash Flood Watch for the Petroleum and Phillips counties.

Wednesday and beyond: Upper low over the Pacific NW then moves NE into the Prairie Provinces of Canada while the upper ridge rebounds over eastern Montana. This should keep temps warmer than normal with small chances for showers and storms. TFJ

FORECAST CONFIDENCE & DEVIATIONS: Gnerally did not deviate from NBM, but did lower Min RH for today a bit. TFJ

AVIATION

UPDATED: 2040Z

FLIGHT CATEGORY: VFR

DISCUSSION: Mainly dry weather and mostly clear skies are expected over the TAF cycle. However, showers and thunderstorms are expected to affect KGGW after 03z Tuesday night.

SFC WIND: NE winds will not decrease at KOLF, KSDY and KGDV till after 06z tonight. Then winds increase from the East at all locations Tuesday. TFJ

GGW WATCHES/WARNINGS/ADVISORIES

Heat Advisory until 2 AM MDT Wednesday for Central and Southeast Phillips-Central and Southern Valley-Garfield-McCone-Northern Phillips-Northern Valley-Petroleum-Southwest Phillips-Western Roosevelt.

Lake Wind Advisory from 10 AM Tuesday to noon MDT Wednesday for Central and Southeast Phillips-Central and Southern Valley- Garfield-McCone-Petroleum.

Flood Watch from Tuesday evening through late Tuesday night for Central and Southeast Phillips-Petroleum-Southwest Phillips.

Heat Advisory until 2 AM MDT Tuesday for Daniels-Sheridan.

Extreme Heat Warning until 2 AM MDT Tuesday for Dawson-Eastern Roosevelt-Richland.

Heat Advisory from 2 AM Tuesday to 2 AM MDT Wednesday for Dawson- Eastern Roosevelt-Richland.

Extreme Heat Warning until 2 AM MDT Thursday for Prairie-Wibaux.