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fxus63 kgrr 141803 
afdgrr

Area forecast discussion
National Weather Service Grand Rapids Michigan
203 PM EDT Mon Oct 14 2019

Latest update...
aviation

Synopsis...
issued at 308 am EDT Mon Oct 14 2019

-areas of frost Tuesday morning with rain arriving during the day

-blustery with lake effect rain showers Wednesday

-dry period from Thursday into at least Friday

-unsettled weather possible especially toward the end of the
weekend into early next week

&&

Update...
issued at 1037 am EDT Mon Oct 14 2019

We're still in a cyclonic flow/cold advection pattern, so suspect
lake related cloudiness will increase and spread farther inland
as we head into the afternoon. Could even be an isolated shower or
two. However after 4 PM or so, sfc ridging will be moving in from
the south and west and this should begin a decreasing cloud
pattern over much of the area as we approach the evening hours.
Probably the most notable weather feature today though is the
lighter wind speeds as compared to previous days.

&&

Discussion...(today through next sunday)
issued at 308 am EDT Mon Oct 14 2019

Our next risk for rain will arrive on Tuesday as an area of low
pressure steadily deepens as it moves from central WI to Lake Huron.
The more favorable upper level jet divergence will be located across
the u.P. And northern lower Michigan with this system. With the h850 low
moving across northern WI/northern lower Michigan it makes sense that the
heavier precipitation will be north of our region. There is a small
window where we could get some rumbles of thunder 18z Tue through
00z Wed as shown by projected MUCAPE by the medium range guidance.
Otherwise, rain showers can be expected at times Tuesday afternoon
and evening especially. Wrap-around lake effect rain showers and
blustery conditions are expected Wednesday as the low deepens into
the mid 990s over Lake Huron. In other words, very October-like.

Prior to this system's arrival, frost is looking like a possibility
Tuesday morning away from the Lakeshore. Some subfreezing
temperatures are not out of the question across interior central
lower Michigan. The next threat for frost would occur Friday morning.

Medium range deterministic guidance and respective ensemble members
(ecm/gefs/geps) suggest a mild and wet pattern is possible across
the Great Lakes toward the end of this weekend and into early next
week. Too soon to talk specific amounts of rain but the upper level
pattern (deep southwest flow with an open feed of Gulf moisture
potentially) would support anomalously high precipitable water
values.

&&

Aviation...(for the 18z tafs through 18z Tuesday afternoon)
issued at 200 PM EDT Mon Oct 14 2019

VFR conditions will continue through 18z Tuesday. The lake effect
clouds currently blanketing the region have bases between 3500 and
6000 ft. These clouds will scatter out across the majority of the
area after 21z leaving mostly clear skies. Exception will be at
mkg where the lake clouds could linger as late as midnight before
low level winds turn offshore/south-southeasterly.

Some mid and high level clouds may move in after midnight
tonight with bases above 12,000 ft. Cloud cover increases
Tuesday, but bases should remain above 5000 ft through 18z. The
outlook beyond 18z Tuesday is for lower MVFR cigs and showers to
arrive from the west.

West sfc winds around 10 kts diminishing tonight and becoming
light southerly. Winds Tuesday increasing out of the southeast to
12-22 kts with some higher gusts in the afternoon.

&&

Marine...
issued at 308 am EDT Mon Oct 14 2019

Will continue the Small Craft Advisory as is, but there is potential for an earlier
cancellation depending on how quickly the winds/waves settle down.
The reprieve will be brief, however, with winds picking up Tuesday
(s/SW flow event) and waves reaching 4 to 7 ft mainly north of
Grand Haven. Conditions worsen Wednesday (nw flow event) with
Lakeshore-eroding waves of 7 to 11 ft once again battering much
of our coastline.



&&

GRR watches/warnings/advisories...
Michigan...frost advisory from 2 am to 8 am EDT Tuesday for miz037>040-
043>046-050>052-056>059-064>067-071>074.

Lm...none.
&&

$$

Update...Meade

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