textproduct: Grand Forks

KEY MESSAGES

- Near critical fire weather today Baudette to Wadena where RH values drop to below 20 percent. Near to critical fire weather possible for some locations Wednesday and Thursday. - Severe weather possible Thursday.

UPDATE

Issued at 1251 PM CDT Tue Apr 21 2026

Continued fairly quiet in the immediate term, but southerly winds will be increasing tomorrow as low pressure develops to our west. While the south to southeasterly winds will also be bringing in higher dew points, there will be a bit of a lag between when winds kick up and higher moisture arrives. Best chances for lower than 30 RH values and the breezier winds are in southeastern North Dakota and portions of west central and northwestern Minnesota. Will be putting out a fire weather watch for those locations.

UPDATE Issued at 644 AM CDT Tue Apr 21 2026

Update to aviation section for 12z TAFs.

UPDATE Issued at 404 AM CDT Tue Apr 21 2026

Despite winds today 5 mph in eastern fcst area, sub 20 pct RH values and dry fuels will prompt a SPS for near critical fire wx conditions as requested by user. Wednesday mid aftn and evening to see advance of 850 mb moisture and low level jet aiding in development of a few showers and thunderstorms as band of 1200 j/kg MUCAPE spreads north 21z Wed to 06z Thu period. But development/coverage of these storms may be limited in coverage. Day 3 from SPC has northwest and west central MN in marginal risk for severe Thursday in advance of a 850 mb dry push eastward thru SE ND into MN...with arc of CAPE north thru MN then wrapping back westward thru far northern ND toward upper low in western ND. Chance of rain/snow mix is limited to DVL basin Thu late night into Friday with no snow accumulation or impacts.

..Synopsis

A low amplitude ridge remains fixed across the western 2/3rds of the CONUS today with an upstream large low off the pacific coast. While ridging remains dominant through the mid week troughing does eventually emerge from the northern and central rockies by Wednesday evening with some scenarios bringing a closed upper low to the Dakotas Thursday and an attendant chance for severe weather. As troughing digs across the existing ridging slow across CONUS becomes zonal with minimal steering of the now occluded upper low to our north or potentially even directly over us (implications on temperatures and rain chances). While clusters do little to capture its exact position or depth by the end of forecast period they all keep it near our area with any shortwave activity well to our south, along with any warmth through the weekend.

- Fire Weather

The ongoing Red Flag today doesnt need to much detail but overall low RH across all of our Minnesota counties especially west central where RH is already widely under 30% from Fergus Falls to Bemidji. Winds are nearing their peak for the day with gusts dropping off by 6pm and sustained winds falling below 15kts by 7pm. Overall the RFW may be slightly larger than weather conditions would currently verify but fuel conditions support it nonetheless. Tomorrow will maintain the low afternoon RH of 25-35% for much of the region (locally lower) through winds will be up to 15kts and thus only near critical conditions mainly across west central Minnesota where fuels are primed.

With limited precipitation expected through the midweek and ridging amplifying across the Northern Plains, ERC maximums should continue to rise with HRB values indicating ongoing dead fuels. At this time, the timeframe of greatest concern is Wednesday afternoon. While NBM relative humidities appear fairly high (30-35%), this is mainly due to limited CAM impact on NBM output and will likely fall towards more critical criteria as we get closer to mid-week. At the same time strong southerly winds of 20kts gusting 30kts are likely. The heightened fire weather pattern will eventually end as widespread precipitation pushes into the region late week.

- Thursday Weather Bingo

Get those spring weather bingo cards ready. Thursday is gonna throw just about everything at the northern plains with an upper low moving into the ND/MN vicinity by the afternoon coincident with diurnal heating. With it may be a narrow ribbon on surface based instability on the order of a few hundred to 1500j/kg of MLCAPE and shear profiles typical of cold core severe weather events. Strong low level curvature near the low and back mid/upper level profiles leading the superb storm relative venting of precip and great low level stretching. Would think all severe hazards are possible if this scenario unfolds. If something more tame or misaligned occurs then a ceiling may be more in the marginal severe to general thunderstorm territory in the afternoon. In either case strong southerly winds through the morning will transport warm dry air north with afternoon Min RH in the 30-35% range (likely too high due to a lack of CAM influence as discussed above) with over lapping 25kt gusting 35kt winds. There is a low chance to reach Wind Advisory criteria in our west/SW Thursday but medium chance for critical fire weather. Further west in ND Precip on the west/SW side of the low will be of a more frozen variety with snow with snow overlapping with strong winds. While we initially start out with rain and thunderstorms Thursday afternoon temps quickly fall from the 60s and 70s around noon to the 30s by sunrise Friday. This will promote a wintry mix overnight into the day on Friday with the best chance (30% chance) for any accumulating snow in the Devils Lake Basin.

Things remaining seasonably cool through the weekend into early next week as the upper low stalls over us/north of us with mostly cloudy skies through the period and highs looking to stay in the 40s and 50s. Lows will at the same time will be in the 20s and 30s so for you ambitious gardeners be sure to bring in any sensitive plants you may already planted. Seasonal frost/freeze headlines will likely start up in the next 2 weeks.

AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/

Issued at 1251 PM CDT Tue Apr 21 2026

VFR conditions now and for the rest of the period with a few high clouds moving through. Winds will be the main concern with the current light and variable winds shifting to the south to southeast overnight. By the end of the period, gusts up to 25 kts will be possible for at least some of our airports.

FGF WATCHES/WARNINGS/ADVISORIES

ND...Fire Weather Watch from Wednesday afternoon through Wednesday evening for NDZ049-052-053. MN...Fire Weather Watch from Wednesday afternoon through Wednesday evening for MNZ017-024-028>032-040.