689
FXUS63 KGRR 161921
AFDGRR

Area Forecast Discussion
National Weather Service Grand Rapids MI
321 PM EDT Mon Sep 16 2024

.KEY MESSAGES...

- Dry and Warm Weather Continues This Week

&&

.DISCUSSION...
Issued at 320 PM EDT Mon Sep 16 2024

Short term: Ridging and dry air continues to dominate aloft and
at the surface with mainly clear skies and light winds. Slightly
cooler H8 temps are shown to arrive from the east on Tuesday so
highs should be a few degrees cooler but still well above normal
in the lower 80s. Large diurnal swings continue with nighttime
temps remaining on the cooler side and not too far off normal due
to the dry air with dew points in the upper 40s/lower 50s. Some
late night/early morning patchy shallow ground fog possible again
especially eastern sections.

Long term: High pressure will remain entrenched over the region
for the week and into next week. Multiple systems, including the
remnants of Francine and for potential Tropical Cyclone Eight,
will try to infiltrate into this ridge this week. Those systems
will fail, with the effects for Michigan being only a slight
reduction in temperatures due to flow around the ridge bringing in
slightly cooler 850mb temperatures.

A ridge through the central United States extending from southern
Texas will tilt positively due to the effects of a large upper
level low moving through the inter mountain west mid to late week.
That low will bring a chance for precipitation as it attempts to
move into the region over the weekend into early next week.
However ensembles and model guidance vary on its track so there is
a good chance SW Michigan remains warm and dry.

&&

.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 227 PM EDT Mon Sep 16 2024

High pressure will continue to dominate the weather through the
period. There will be a brief period early tomorrow morning with a
narrow window of MVFR vsbys, between 09Z and 13Z. As the region
continues to get drier by the day this area shrinks. JXN, AZO, BTL
and LAN are possible with JXN having the best chance of seeing
MVFR vsbys. Any reductions will be short lived with light winds
continuing tomorrow.

&&

.MARINE...
Issued at 320 PM EDT Mon Sep 16 2024

Light wind regime continues over Lk MI thanks to continued
surface ridging. Winds generally 5-10 kts; offshore at night into
the morning, then onshore during the afternoon and early evening
due to the diurnal lake breeze circulation.


&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...None.

&&

$$

DISCUSSION...Meade/Ceru
AVIATION...Ceru
MARINE...Meade