Area Forecast Discussion
Issued by NWS Grand Forks, ND
Issued by NWS Grand Forks, ND
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341 FXUS63 KFGF 150337 AFDFGF Area Forecast Discussion National Weather Service Grand Forks ND 1037 PM CDT Sun Jul 14 2024 .KEY MESSAGES... - There is a level 2 out of 5 risk for severe thunderstorms west of the Red River Valley overnight tonight. && UPDATE Issued at 1003 PM CDT Sun Jul 14 2024 Clusters of strong to severe thunderstorms are just west of the Devils Lake Basin this evening and are tracking southeast. Past storms that have entered the Devils Lake Basin have diminished in intensity as the airmass over the Basin has been relatively stable. So we are watching the current storms to see if they will be able to push into the Basin and retain their severity. A secondary area is further toward the west that is pushing eastward toward the area. RAP/HRRR/NAM guidance continues to push the instability and higher convective potential area eastward over the course of the next several hours. This would increase the threat for severe thunderstorms in the Devils Lake Basin towards the Sheyenne River Valley. The message still remains the same, with the main hazards being hail up to golf ball size and damaging winds up to 75 mph. UPDATE Issued at 628 PM CDT Sun Jul 14 2024 A Severe Thunderstorm Watch was issued till midnight for Cavalier, Towner, Ramsey, and Benson counties. We see clusters of storms developing in Manitoba and north central North Dakota this evening tracking south and east. Time of arrival within the Devils Lake Basin is between 9 and 11pm. They are moving into a more stable airmass as they track eastward. Uncertainty with the progression of instability eastward overnight which would affect the strength of the storms. However, CAMs continue to indicate the storms developing further into bowing segments or a linear complex as we continue through the evening hours. We will continue to monitor the threat for severe weather. && .DISCUSSION... Issued at 333 PM CDT Sun Jul 14 2024 ...Synopsis... Satellite shows some mid-level and higher level clouds working their way ESE from Saskatchewan this afternoon. Some fields of cumulus are trying to bubble up as the ground warms, resulting in a few pockets around the area. Later this evening, a surface low pressure system will traverse the area, providing the forcing for our expected severe risk. The actual upper low (further back in AB and SK) is expected later on Monday, but instability and other necessary parameters during that period look to be lower, so not thinking severe weather with the UL. Once we get to mid-week, the pattern is expected to shift to ridging to our SW and calmer weather for the work week. ...Severe Risk & Beyond... For the severe risk, guidance has pivoted to show more of an overnight event, with some discrete cells ahead of the actual line of storms. Hazards such as large hail and damaging winds are still expected, but given the predominantly cluster nature, hail size is likely closer to ping pong ball sized (1.5") rather than golf ball sized (1.75"). This is not to say golf balls are not possible in discrete cells that can maintain nuclei in the ice growth zone. MUCAPE remains sufficient for convection, around 1000-2000 J/kg, and shear is more than enough to support strong storms around 50 knots. Damaging winds are a concern with DCAPE over 1000 J/kg in the southern valley, and with dry air aloft, would not be surprised to see some 70 MPH gusts. Some heavy rain is possible as well, with 40 - 60% chance of greater than or equal to 0.5" in 24 hours, mainly HWY- 200 and north on the ND side. After this trough, the rest of the week features quiet weather, and cooler temperatures, warming into the mid 80s by the weekend. && .AVIATION /00Z TAFS THROUGH 00Z TUESDAY/... Issued at 1037 PM CDT Sun Jul 14 2024 Storms are appoarching the Devils Lake Basin this evening and will continue to spread eastward overnight. TSRA and erractic winds will be likely when storms arrive within the next several hours for DVL. They shift into the Red River Valley affecting TVF, GFK, and FAR around 08-11z, followed by BJI around 10-11z. They exit northwestern Minnesota after 13-15z. Ceilings reach MVFR to IFR underneath storms and after storms pass for several hours before skies turn FEW to SCT for coverage. Winds turn toward the north tomorrow afternoon, with isolated gusts up to 20kts possible for DVL, FAR, GFK, and TVF. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. && $$ UPDATE...Spender DISCUSSION...AH AVIATION...Spender