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Area forecast discussion
National Weather Service Marquette Michigan
614 am EDT Thu Jun 21 2018

Short term...(today and tonight)
issued at 318 am EDT Thursday Jun 21 2018

Split flow pattern continues aloft with Great Lakes in the dry and
quiet northwest flow of the northern stream downstream of ridge
that extends as far north as northwest territories of Canada.
Strong upper low in the southern stream is leading to heavy
rain/flooding over parts of SD/NE/IA/MN. Arcs of rain showers
lifting ahead of the upper low are still south of Green Bay and
the Twin Cities early this morning and expect the rain to remain
well to south of Upper Michigan into tonight. Only high clouds of
note will be over far south with skies sunny elsewhere. High
pressure that built over area on Wed aftn will be overhead today,
centered over eastern lk Superior and toward James Bay. Result
will be easterly component winds over all of Upper Michigan today.
Coolest temps in the 60s will be close to lk Superior, especially
east of Keweenaw to around Munising. 850 mb temps slightly cooler
than Wed at 12-13c this aftn, but should still see temps inland
toward the 80 degree mark. East flow typically is dry and have
went the guidance showing lower TD/relative humidity to account for that today.

With the ridge still close by tonight leading to light winds and
clear skies, expect temps most areas to drop into the 40s. Coolest
spots over interior could drop as low as 40f.

Long term...(friday through wednesday)
issued at 247 am EDT Thursday Jun 21 2018

The NAM has a closed 500 mb low over central Illinois 12z Fri which is
topped by a shortwave ridge over the upper Great Lakes and there is
another shortwave over the northern rockies. This closed low gets
absorbed into a trough that digs into the ern U.S. Sat night. Quiet
for this forecast with no changes made.

In the extended, the GFS and European model (ecmwf) show a 500 mb ridge over the
northern plains 12z sun with a trough over the ern U.S. And a closed
low over the central rockies. A backdoor cold front will have moved
through the area earlier on Sunday. The ridge moves into the upper
Great Lakes on Mon and remains into Tue as a closed low moves out
into the Central Plains. The closed low and associated trough moves
into the upper Great Lakes on Wed. Upper ridging starts to move back
in on Thu as a cold front moves through the area.

Aviation...(for the 12z tafs through 12z Friday morning)
issued at 613 am EDT Thursday Jun 21 2018

With a dry air mass over the area, VFR conditions will prevail at
kiwd/kcmx/ksaw through this forecast period. Winds will be light.


Marine...(for the 4 am Lake Superior forecast issuance)
issued at 318 am EDT Thursday Jun 21 2018

Winds will remain at or below 20 knots through the forecast period.

MQT watches/warnings/advisories...
Upper Michigan...
Lake Superior...
Lake Michigan...


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