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Area forecast discussion
National Weather Service Gaylord Michigan
1144 PM EDT sun Jul 21 2019

Update...
issued at 932 PM EDT sun Jul 21 2019

Shroud of mid/high clouds is making healthy inroads into much of
northern lower mi, ahead of schedule. Eastern Upper Michigan is seeing
less of this, at least so far. Cloud cover has generally been
increased. Otherwise few changes are needed, with a quiet and
cooler night ahead.

&&

Near term...(through tonight)
issued at 334 PM EDT sun Jul 21 2019

..quiet and comfortable tonight...

High impact weather potential: none.

Pattern synopsis/forecast: afternoon surface analysis shows a
large expanse of high pressure continuing to build across the
northern Great Lake...out of the northern plains/southern Canada
region. Drier low level air is now making it's way into northern
Michigan with surface dewpoints dropping into the 50s in many
areas in the last several hours. There is a fair amount of
"heating of the day" cloud cover across the region (particularly
western upper michigan) along with some high cloud cover streaming
through.

Upstream, mid level short-wave is evident across the northern
plains moving into the upper Midwest, on the heels of an upper
level jet streak punching into the northern Great Lakes. That
feature will play a role for tonight.

Larger scale mid level flow will buckle across the Great Lakes
later tonight into Monday courtesy of the aforementioned mid
level short-wave sliding into the northern Great Lakes. Short-
wave and upper jet forcing will spread thicker mid and high cloud
cover across the region later tonight into Monday (cloud cover is
organizing across the Dakotas into minnesota). There are some
radar returns upstream and some of the earlier high-resolution
guidance hinted at the possibilities of some very light precip
sliding through the region overnight. But forecast soundings are
just not that impressive from a saturated layer standpoint. So
while I will have a period of thicker cloud cover, i'll maintain
the dry forecast.

&&

Short term...(monday through wednesday)
issued at 334 PM EDT sun Jul 21 2019

High impact weather potential: minimal.

Pattern synopsis/forecast: by Monday morning, vertically stacked
closed upper-level low pressure is expected to be spinning near
James Bay with broad troughing encompassing much of the Great Lakes
region. This pattern is expected to continue right on through
Tuesday before heights begin to rise Tuesday night-Wednesday as weak
ridging slides across the region from the west. At the surface, high
pressure is progged to be nosing into the region from the west
throughout much of the forecast period, leading to a stretch of
rather tranquil conditions overall.

Primary forecast concerns/challenges: slight chance of a shower
Tuesday afternoon?

Weak cold air advection will be ongoing through much of the day
Monday under broad north-northwesterly flow as high pressure slowly
nudges into the forecast area from the west. Mostly to partly sunny
skies are expected to be the rule with noticeably cooler
temperatures...some 5 or so degrees below mid-late July normals as
highs range from the low-mid 70s area-wide.

Primarily dry weather continues through the remainder of the
forecast period with slowly increasing daytime high temperatures
(mid-upper 70s Tuesday and low 80s Wednesday, for most). The only
possible blemish foreseen at this point revolves around the Tuesday
afternoon time frame as a shortwave trough treks through larger
scale parent troughing, along with a pocket of deeper moisture. The
combination may be enough to kick off a few light/isolated afternoon
and early evening showers across interior sections of northern lower
Michigan. Think most areas stay rain-free, but at the very least will add
a slight chance of a shower into parts of north-central and
northeast lower for Tuesday afternoon.

Long term...(wednesday night through sunday)
issued at 334 PM EDT sun Jul 21 2019

High impact weather potential: minimal.

Broad northwesterly flow continues through Wednesday night with
little in the way of impact. Could foresee a solution that brings a
few more light/scattered showers to portions of the forecast area
Thursday and again Friday, but with little confidence at this point
given subtle guidance differences with respect to timing/strength of
embedded shortwaves in large scale flow. Perhaps the next widespread
chance of showers and storms arrives late in the week into next
weekend as a cold front is expected to drop across the region during
the Saturday/Sunday time frame.

&&

Aviation...(for the 06z tafs through 06z Monday night)
issued at 1143 PM EDT sun Jul 21 2019

VFR.

Large high pressure in ND is extending ridging into the northern
Great Lakes. This has brought cooler and drier air into the
region. An upper level disturbance will spread mid and high clouds
into northern Michigan overnight, but conditions will remain VFR into
and thru Monday.

Mainly NNW winds. These will be a touch gusty on Monday
afternoon.

&&

Marine...
issued at 334 PM EDT sun Jul 21 2019

Gustier northwest winds will be felt on the lakes through this evening.
Gust will occasionally approach Small Craft Advisory levels (22
knots) on Whitefish Bay and Northern Lake Huron.

Winds diminish later tonight but increase again on Monday with
gusts more solidly in the Small Craft Advisory range. Small craft
advisories will likely be needed on Northern Lake Huron for Monday
and possibly parts of Northern Lake Michigan.



&&

Apx watches/warnings/advisories...
Michigan...none.
LH...none.
Lm...none.
Ls...Small Craft Advisory until midnight EDT tonight for lsz322.
&&

$$

Update...jz

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