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Area forecast discussion
National Weather Service Gaylord Michigan
345 PM EDT Sat Aug 24 2019

Near term...(through tonight)
issued at 345 PM EDT Sat Aug 24 2019

..quiet and cool again tonight...

High impact weather potential: minimal. Some fog/status possible

Pattern synopsis/forecast: afternoon analysis reveals a sharp
short-wave ridge axis from the Midwest up through the far western
Great Lakes, part of a pseudo Omega block pattern across the
region. Strong surface high pressure is centered just northeast of
state with easterly flow cycling cool/dry air through the region.
We have seen some heating of the day cumulus develop across inland
areas, although overall sunny/mostly sunny skies are the rule.

Primary forecast concerns: overnight lows and fog/stratus

Sharp short-wave ridge and surface high pressure will edge off to
the east tonight while our low level flow veers southeasterly and
increases just a bit. Heating of the day cumulus fades early this
evening leading to clear skies and another good radiational
cooling setup. That said, moderating low level temperatures and the
slight increase in low level flow may counteract radiational
cooling to some degree particularly across the western part of the
forecast area. So for tonight...I have the coolest overnight lows
across interior eastern upper and northeast lower Michigan with
those areas dipping into the upper 30s to lower 40s while
acknowledging that we will probably have a few spots dip into the
middle 30s once again (atlanta, Mio, etc).

Fog/stratus: given our afternoon min dewpoints (crossover temps)
of 45 to 50, anticipated lows and a decoupled boundary layer,
some fog seems reasonable, especially across eastern upper and NE
lower Michigan where the lowest temps are anticipated. Eventual low
level southeast warm/moist flow off Lake Huron overtop a cool boundary
layer may add to the fog or even stratus potential. Will see. But
I have added patchy-areas of fog to the forecast as well as some
increasing cloud cover (stratus) toward morning.


Short term...(sunday through tuesday)
issued at 345 PM EDT Sat Aug 24 2019

..a better chance for rain on Monday night/tuesday?...

High impact weather potential...thunder possible Monday evening.

Pattern synopsis/forecast...high pressure over the upper Great Lakes
begins to slip east, allowing the return flow to move into the
state. Winds will increase as the pressure gradient tightens. This
will lead to stronger winds near The Straits, initially, but then
spread across the region Monday afternoon, as the warm front passes
through lower Michigan. Rain showers are expected in the afternoon,
but the main precipitation comes in Monday evening (after 00z/tue)
as a 500 mb shortwave moves into the region with the front. The cold
front and the sfc trough, associated with the sfc low move through
by 12z/Tue bringing rain showers, and maybe some thunder. The rain
looks to clear out by Tuesday afternoon as some shortwave ridging
and dry air quickly noses into the region.

Primary forecast concerns...this could be the best chance for rain
that we have seen in a while. However, as we have seen in the past
few weeks, the models have been having trouble with the frontal
passages. However, this looks to be more a concerted effort for the
500 mb low and jet to sink into North Plains and the upper Great Lakes.
Since we are beginning to head into the fall season, this does look
to be more a fall type system. The 850 mb temperatures associated
with this system(upstream) are in the mid single digits so there is
better certainty with this system.


Long term...(tuesday night through saturday)
issued at 345 PM EDT Sat Aug 24 2019

High impact weather potential...minimal

Extended (tuesday evening through saturday)...after the brief warm
up for early part of the week, as the we get into the middle of the
week, there is a cooling trend with the long wave pattern. A decent
500 mb low drops south into northwest Ontario, just west of James Bay, on
Tuesday night, which looks to brings with it 850 mb temperatures that
are sub +5c. As that air and the sfc low moves into Lake Superior,
+6c/+7c air moves over Lake Michigan and its +21c water
temperatures. We may be looking at le rain possibilities for
Wednesday and Wednesday night, before high pressure and dry air
Thursday move in. However, there are some timing issues with the GFS
and European model (ecmwf) so that small rain chances continue through Thursday and
Friday. Friday night and Saturday, high pressure builds into the
region and it looks like it dries out again.


Aviation...(for the 18z tafs through 18z Sunday afternoon)
issued at 238 PM EDT Sat Aug 24 2019

Strong high pressure across the region will provide solid VFR
conditions through Sunday morning. That said, some shallow fog
will again be possible particularly across north-central and NE
lower Michigan.

Otherwise, light winds this afternoon and tonight. Southeast winds pick
up some Sunday afternoon.


issued at 345 PM EDT Sat Aug 24 2019

Light winds and waves anticipated tonight. Some southeast gustiness
develops on Sunday and it might be enough to consider small craft
advisories up through The Straits. But stronger flow comes on
Monday and it appears that small crafts will be needed for many
nearshore areas at that time.

Weather-wise, quiet tonight through Sunday night. Shower chances
return Monday.


Apx watches/warnings/advisories...


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