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fxus63 kgrr 172336 
afdgrr

Area forecast discussion
National Weather Service Grand Rapids Michigan
736 PM EDT Tue Sep 17 2019

Latest update...
aviation

Synopsis...
issued at 300 PM EDT Tue Sep 17 2019

- fair and unseasonably warm weather mid to late week

- patchy fog very late tonight and early Wednesday

- next chance for rain late Saturday through Sunday

&&

Discussion...(this evening through next tuesday)
issued at 300 PM EDT Tue Sep 17 2019

Fair and unseasonably warm wx is forecast mid to late week as the
upper level ridge amplifies over the Great Lakes region. Vis Sat
trends this afternoon show the band of stratus over our eastern
fcst area that was trapped under the strong low level temp
inversion continues to shrink.

High res model guidance cloud progs such as that from the href
and 3km NAM suggest some areas of stratus will redevelop late
tonight into Wednesday morning largely due to the east to se wind
component off of Lake Huron and Lake Erie. Some patchy fog will
develop overnight as well.

A consensus of latest medium range guidance continues to suggest
that the next chance for rain will not come until late Saturday
through Saturday night and Sunday along and out ahead of an
approaching cold front from the west. Depending on exact frontal
timing instability could be sufficient enough for some scattered
convection as well. Temps will cool off a bit early next week but
will still average a little above normal for that time of year.

&&

Aviation...(for the 00z tafs through 00z Wednesday evening)
issued at 737 PM EDT Tue Sep 17 2019

VFR conditions will prevail this evening then shallow fog will
bring some areas of IFR after midnight. The fog will dissipate
after sunrise with VFR conditions on Wednesday. East winds less
than 10 knots tonight turning southeast on Wednesday.

&&

Marine...
issued at 300 PM EDT Tue Sep 17 2019

Fog has dissipated and wind speeds and wave heights will remain
quite minimal through midweek. Some patchy fog may develop again
late tonight into Wednesday morning.

&&

GRR watches/warnings/advisories...
Michigan...none.
Lm...none.
&&

$$

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