textproduct: Grand Rapids

KEY MESSAGES

- Decreasing clouds and warmer today

- Increasing chances of showers/storms beginning Friday night

- Summer-like temperatures on the way

DISCUSSION

Issued at 238 AM EDT Thu May 14 2026

- Decreasing clouds and warmer today

As mentioned below, quite a bit of stratocu continues to rotate southward around the departing upper low. However, recent images shows some breaks developing across the cloud mass, especially over northern Lake Huron. Still expecting clearing skies this morning leading to a party cloudy day. As upper ridging moves in from the west, heights and temperatures will increase. H8 temperatures begin today around 0c across the cwa and rise to 6c by evening. This increase will be reflected on the surface with highs in the upper 60s today.

- Increasing chances of showers/storms beginning Friday night

Quasi zonal flow beginning Friday night will enable short waves to traverse the region. Roughly half of the Euro ensembles produces a hundredth or two of precipitation Friday night, but HRRR soundings look pretty dry which suggests that virga may be the result of the minor waves moving through.

Saturday, a warm front will be lifting northward across the OH/TN valleys with showers/storms developing along it over Indiana. It's possible a few of these storms could push north into the southern couple of rows of counties late in the day.

Strengthening low pressure over the Plains will push the warm front through the cwa Sunday and chances for showers/storms will increase. Moisture transport vectors increase Sunday afternoon and precipitable water values increase to 1.75 inches. SBCAPE also increases to 1500 j/kg. However, shear values are only progd around 30 kts. This will likely limit severe potential Sunday; higher values were noted west of the lake. We'll have to wait until Monday/Tuesday before the Plains low pushes a cold front through the cwa to see the highest chances for precipitation across the cwa. Even then though, NCAR medium range AI convective hazards forecast indicates severe chances will be west of the cwa.

- Summer-like temperatures on the way

H8 temperatures will rise to 16c by Monday. This should push temperatures well into the 80s...perhaps close to 90. Dewpoints in the 60s will make it feel summer-like early next week. Highs will be in the 80s Saturday and Sunday as well. Even after the cold front moves through next week, highs are still progd in the 70s.

AVIATION /18Z TAFS THROUGH 18Z FRIDAY/

Issued at 129 PM EDT Thu May 14 2026

VFR conditions will dominate the pattern over the next few days. There will some partly cloudy skies but nothing substantial. Winds will go calm this evening and then mix out out of the south after sunrise. Gusty winds out of the south to southwest are expected at all TAF sites tomorrow after 15Z.

MARINE

Issued at 238 AM EDT Thu May 14 2026

An upper ridge is building over the Great Lakes and will keep wind and waves below advisory criteria today and tonight. However as it moves east Friday, the gradient will tighten and south winds will increase resulting in waves that build to 3 to 5 feet north of Holland; a small craft advisory will likely be needed Friday afternoon through Friday night.

GRR WATCHES/WARNINGS/ADVISORIES

MI...None. MARINE...None.