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KEY MESSAGES

- Isolated to scattered severe thunderstorms are possible this evening in western and parts of central North Dakota. The main hazards are hail up to 2 inches in diameter and wind gusts up to 70 mph.

- Isolated severe thunderstorms are possible again Monday in the southeast.

- Periodic chances of showers and thunderstorms will continue this week, with the highest chances on Tuesday.

- A cooling trend will begin Monday and continue through midweek. A warming trend will resume by late this week.

UPDATE

Issued at 658 PM CDT Sun Jul 5 2026

Severe Thunderstorm Watch remains for portions of western and north central North Dakota until 11 PM CDT / 10 PM MDT. Watch was recently expanded into southwestern ND as well. Overall multicluster storms have displayed pulse like tendencies, with few of these storms briefly showing supercell like structure. With ample CAPE and DCAPE hail and winds will remain the main threat. Somewhat straight hodographs indicate limited SRH available for tornadoes, thus the tornado threat remains low. As these storms push eastward they may outrun the higher amounts of shear along the ongoing boundaries. Thus the forecast is for storms to weekend later in the evening. For now anyone in a Severe Thunderstorm Watch should remain weather aware through this evening.

UPDATE Issued at 410 PM CDT Sun Jul 5 2026

Severe Thunderstorm Watch issued for portions of western and north central North Dakota with thunderstorm development expected in these areas the next 1 to 2 hours. Strong surface heating will erode some capping this afternoon, although slight mix layer capping may remain. Satellite showing a line of convection trying to develop in McKenzie county currently, with another boundary near parallel to Highway 2 north, with some billow clouds on the western extent of this line. Where these two boundaries set up and especially meet will be the likely area to monitor for severe storms through this evening. High amounts of CAPE with modest to high shear will provide for a hail threat up to two inches in diameter with any rotating supercells. Multi- cluster storms may dominate today, although some supercells are possible in the mentioned north-south boundary currently setting up in McKenzie county and southward. High DCAPE over 1000 J/KG and 0 to 3 KM shear over 20 knots would indicate strong winds also likely with any storms. A more linear mode of storms, potentially in the west- east boundary in the north could perhaps see winds 70 mph or higher. Elevated storms would also have high wind potential with some inverted v forecast soundings showing up. Tornado threat is overall low. There is some high STP in the northwest where the billow clouds are showing up on satellite. This area is likely behind the mentioned northern front, thus surface based storms might be tough to develop. Elsewhere STP is low and hodographs are not favorable. Some supercell interaction can always change this threat, thus will continue to message a low tornado threat.

DISCUSSION

Issued at 245 PM CDT Sun Jul 5 2026

Currently a large ridge is over the Central Plains, with slight southwesterly flow over Montana. The ridge axis is over eastern North Dakota, with the southwest flow moving into western North Dakota. At the surface a weak low pressure is drawn in eastern Montana, with a front and surface trough draped south to north across eastern Montana. Southerly flow at 850mb is bringing in the very warm air into the Northern Plains, and the southwest flow is bringing the Pacific Northwest moisture in.

The storm potential continues to look to be in the west and north today as the southwest flow and surface trough move east into the state. We have a level 1 risk across most of the west, and a level 2 in the north central. Dew points in the northwest and north central will be in the mid to upper 60s, along with surface temperatures in the low 90s. This will create an axis of 1500 to 3000 J/kg of CAPE across the northwest and north central. With the southwest flow having a tight gradient, the strong winds will create 35 to 50 kts of shear across the same area. Model soundings have a drier low to mid levels, and a slight cap so these may just be elevated storms. Therefore we are only expecting a hail and winds threat. Hail could be up to two inches but that will depend on storm mode. With the drier low and mid levels, the soundings have the classic inverted V look. Wind gusts could be up to 60 or 70mph. For most or all of the event storm mode looks linear based on the CAMs. The larger hail could happen if the storms are isolated before forming into a line. Storm initiation looks to be in a few hours, between 4 and 6pm CT. We are already seeing some billow clouds in far northeastern Montana, moving into far northwestern North Dakota. There is also cumulus clouds attempting to grow north and east of Williston with light radar echos, so maybe the timing is closer to 4pm. Storms look to continue through the night in the north central, severe or not.

Monday there is another severe risk in the east as the surface trough and southwest flow move east. There is a level 1 risk across most of the southeast half of the state. The environment looks similar to today with around 35kts of shear, and at least 1500 J/kg CAPE. Timing looks to be in the late afternoon and evening after the diurnal heating take full effect. Monday will also be a little breezy in the west from the pressure gradient. Starting Monday zonal flow will dominate the Northern Plains, regulating temperatures back into the 70s and 80s. Multiple waves in the flow will bring chances for showers and thunderstorms, and since it is July these storms could be strong to severe. Looking ahead to next weekend, the mid to upper 90s could return as a large Desert Southwest high could form and push the very warm air north.

AVIATION /00Z TAFS THROUGH 00Z TUESDAY/

Issued at 658 PM CDT Sun Jul 5 2026

Showers and thunderstorms could be found and some western and central TAF sites this evening and again overnight tonight. This evenings storms may be strong to severe. Any thunderstorm could bring brief MVFR conditions. Used a mix of TEMPO and PROB30 groups for this thunderstorm threat through tonight. Otherwise look for mainly VFR conditions. Southerly winds will become variable tonight then become north northeast for Monday. Low level wind shear is also possible this evening into tonight as a front moves across the state.

BIS WATCHES/WARNINGS/ADVISORIES

None.