textproduct: Marquette

KEY MESSAGES

- Widespread chances for showers and thunderstorms today and Friday (40-70%). Much lower chances on Saturday (15-25%), only over the east half of Upper Michigan. Severe weather is not expected over the next few days.

- High temperatures increase well into the 80s today, then fall back into the 70s to low 80s Friday into the weekend.

DISCUSSION

Issued at 332 AM EDT Thu Jul 30 2026

Early morning GOES WV imagery and RAP analysis place the UP on the northeastern periphery of a strong mid level ridge over the central CONUS. At the sfc weak high pressure around 1016 mb is centered over northern IL. This is extending weak 1012-1015 mb ridging north- northeast over the UP, Ontario, and into northern Quebec. As a result of the southwest winds and height rises, temps warm up today into the 80s to low 90s. With this WAA and moisture advection, humid conditions and modest instability develops supportive of storms. Timing is a bit blurry as convection has to move over a more stable lake influenced airmass and forcing is somewhat nebulous, but CAMs indicate the moisture convergence and weak dynamics will support some showers and weak storm activity over the west. Likely start time window is 12-15Z timeframe, but a few isolated showers may sneak in ahead of that. These showers/storms continue to expand and press eastward before dissipating toward the later afternoon hours as a disturbance over ND and Manitoba approaches. With lackluster forcing and unimpressive shear, severe weather is not expected. However, heavy downpours yielding isolated rainfall amounts up to 0.5" to 0.75" is possible (30-60% chance); mean rainfall totals of 0.25" or lower are anticipated, highest west half. Otherwise patchy wildfire smoke from the northwestern CONUS may yield hazy skies today into the weekend.

A mid level trough over the Dakotas at the end of today moves over WI Friday into Saturday, interacting with a descending cold front from the northwest. This yields better widespread chances (40-70%) for showers and storms on Friday. Shear will continue to be lacking, keeping the strong to severe threat at bay. This round supports better QPF fields with NBM depicting more widespread coverage of amounts in the 0.25" to 0.5". Temps fall back into the 70s to low 80s on Friday.

A few showers and thunderstorms could linger into early Saturday in the wake of these systems, mainly east half. Do not expect any strong to severe storms for any of these periods as shear remains weak for the next few days. Sunday into Monday favors drier weather a high pressure builds back into the region, with temperatures looking to climb back into the 80s for much of next week. Another approaching trough will bring increasing precipitation chances again towards the middle of next week, but details are sparse at this time.

AVIATION /12Z TAFS THROUGH 12Z FRIDAY/

Issued at 758 AM EDT Thu Jul 30 2026

VFR conditions will generally prevail for the duration of the TAF period. Clear skies give way to increasing mid and upper level cloud cover Thursday afternoon ahead of a couple disturbances, which could bring spotty showers and storms to IWD and CMX during the afternoon and evening. Given low confidence in timing and coverage, have included this in PROB30 groups.

MARINE

Issued at 332 AM EDT Thu Jul 30 2026

Expect winds to remain below 20 kts for much of the next week amidst benign weather. Weak troughing moving back into the region today, bringing a few thunderstorms over Lake Superior and northern Lake Michigan through Saturday. Storms are not expected to be severe.

MQT WATCHES/WARNINGS/ADVISORIES

Upper Michigan... None. Lake Superior... None. Lake Michigan... None.