East Lansing, Michigan 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

856
FXUS63 KGRR 161749
AFDGRR

Area Forecast Discussion
National Weather Service Grand Rapids MI
149 PM EDT Thu Jul 16 2026

.KEY MESSAGES...

- Poor Air Quality and Reduced Visibilities From Smoke Thursday

- Several Chances of Showers and Storms Through Early Next Week

- Temperatures Cooling Through Early Next Week

&&

.DISCUSSION...
Issued at 230 AM EDT Thu Jul 16 2026

- Poor Air Quality and Reduced Visibilities From Smoke Thursday

Primary forecast concern over the next day is impacts from near-
surface and aloft wildfire smoke across the area. ASOS
observations show widespread visibilities in the 1-3SM range as a
result of smoke. Some areas across Lower Michigan have fallen as
low as 1/2SM at times in the last 24 hours, and cannot rule out
similar conditons here as another pocket of near-surface smoke
arrives near daybreak. HRRR/Canadian smoke guidance shows near-
surface smoke persisting through the day today. Air quality
observations show unhealthy to locally hazardous conditions, and
an Air Quality Alert remains in effect areawide from Michigan`s
Department of Environment, Great Lakes, and Energy.

- Several Chances of Showers and Storms Through Early Next Week

A series of fronts and shortwaves drive several shower and
thunderstorm chances through early next week. First is Friday with
a warm front crossing the area. However, low-level moisture
quality is poor limiting precipitation potential. A cold front
Saturday brings greater potential for showers and storms, along
with ample CAPE and decent kinematics. However, ample MLCIN will
help put a check on storm development, with the best chance east
of US-127 into southeast Michigan. Given the ample CAPE/Shear, any
storms that develop could be strong to severe, so forecast trends
will need to be monitored. Another cold front Monday Night into
Tuesday brings a third round of shower/storm chances to the area.

- Temperatures Cooling Through Early Next Week

850mb temps will fall from near 20C over the next day or two to
the low to mid teens by mid next week. This will cause highs to
fall from the low 90s Thursday/Friday to the low 80s by early
next week. With lower post-frontal dewpoints expected after the
front bringing smoke to the area tonight, heat indices will be
limited to the 90s, cooler than previous days.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 149 PM EDT Thu Jul 16 2026

Local surface observations continue to indicate IFR and even LIFR
horizontal visibility restrictions in smoke along with MVFR broken
"cloud" layers that are in reality associated with vertical
visibility restrictions in smoke. It is possible that terminals
experiencing LIFR visibility restrictions will temporarily rise
into the 1+ mile range this afternoon; however, predictability
with smoke and its light scattering effects are very limited. To
illustrate: our chief guidance source for these situations, the
HRRR-smoke model, has been under-forecasting the severity of visibility
restrictions thus far, which does not bode well for significant
improvements in the short term, or even for the full valid period
of this TAF package.

The only change of note was to introduce a period of northwest
winds this afternoon. But even this could be affected somewhat by
atypical diurnal heating effects (and subsequent surface pressure
responses) associated with the smoke.

&&

.MARINE...
Issued at 645 AM EDT Thu Jul 16 2026

Webcams show widespread dense smoke north of Holland with smoke
starting to become dense south of Holland. In collaboration with
other Lake Michigan offices, have issued a Dense Smoke Advisory
through early afternoon. Will let day shift reassess to see if an
extension is needed as daytime mixing develops.

--- Previous Discussion Issued 230 AM EDT Thu Jul 16 2026---

Widespread smoke is expected across the waters with visibilities
below one mile possible at times. If confidence increases in lower
visibilities a Marine Dense Smoke advisory may be needed. Between
Friday morning and Saturday, a series of fronts bring the
potential for isolated thunderstorms over the waters. In addition,
strengthening northwest flow is expected to develop Saturday,
causing waves to build to at least 3-5 ft. This makes it likely
conditions will be hazardous to small craft and boaters.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Air Quality Alert until midnight EDT Friday night for MIZ037>040-
     043>046-050>052-056>059-064>067-071>074.
MARINE...Dense Smoke Advisory until 8 PM EDT Friday for LMZ844>849.

&&

$$

DISCUSSION...Thomas
AVIATION...TJT
MARINE...Thomas