textproduct: Grand Rapids

KEY MESSAGES

- Dry Until Chances for Rain and Thunderstorms Monday Night

- Mainly Dry and Cooler for the Remainder of Next Week

DISCUSSION

Issued at 245 PM EDT Sat Apr 25 2026

- Dry Until Chances for Rain and Thunderstorms Monday Night

Upper level ridging and high pressure will remain in place through the weekend resulting in dry conditions. Southwest flow moves in Monday ahead of the shortwave trough. Upper level divergence, positive vorticity advection, and the low level jet line up for late Monday afternoon into Monday night. There will be plenty of shear in place with the 50 knot low level jet with winds up to 70 knots in the mid levels. The question on our severe potential will largely be up to how much instability is available. NBM mean SBCAPE has instability ranging from a few hundred to a couple hundred J/kg toward US-10 to near 1000 J/kg toward the I-94 corridor. If these instability values remain the same or increase, the SPC outlook would likely trend upward as we get closer. After the initial round of thunderstorms Monday night, some lingering rain showers are possible into Tuesday morning.

- Mainly Dry and Cooler for the Remainder of Next Week

Overall we'll remain under the upper level trough with the potential for a couple shortwave troughs to move through. These troughs could bring some chances (20 percent) for light showers, but moisture is limited with precipitable water values remaining low. Highs through the week are expected to be in the 50s with lows in the 30s bringing the risk for a widespread frost.

AVIATION /00Z TAFS THROUGH 00Z MONDAY/

Issued at 615 PM EDT Sat Apr 25 2026

Upstream satellite and observations indicate drier air is beginning to erode the entrenched MVFR cloud deck across the Thumb region of lower Michigan. LAN and JXN are the two terminals where MVFR cigs persist as of present, and it is likely it will take until mid to late evening for those sites to scatter out. Latest short range model guidance now suggests that the drier air and subsidence from a nearby high pressure system will keep clouds scattered overnight. It is very possible that pockets of greater cloud cover may lead to restrictions at times, as if a BKN deck can be established MVFR cigs are likely with IFR and lower possible. However, confidence in where and when this would occur is to low to indicate restrictions at this time. The potential for restrictions ends Sunday morning when continued subsidence and arrival of dry air causes skies to become mostly clear through the end of the TAF window.

MARINE

Issued at 245 PM EDT Sat Apr 25 2026

Winds are overachieving this afternoon and with an expected trend upward, expect gusts to be in the 25 to 30 knot range until this evening. With this change have issued a Small Craft Advisory until 8PM. Winds are expected to weaken and turn more easterly tonight into Sunday with low wave heights.

Monday winds turn to the southwest with a chance for thunderstorms to move in during the late afternoon and evening. Small craft advisory conditions are likely for Monday into Tuesday. Winds should remain below gales due to the cold waters, however storms could be strong to severe and mix down stronger winds from aloft.

GRR WATCHES/WARNINGS/ADVISORIES

MI...None. MARINE...Small Craft Advisory until 8 PM EDT this evening for LMZ844>849.