794
FXUS63 KMQT 231845
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
245 PM EDT Sun Jul 23 2017

.SHORT TERM...(This evening through Monday)
Issued at 244 PM EDT SUN JUL 23 2017

No major weather impacts expected through the short-term portion of
the forecast; however, larger waves and onshore winds will keep a
moderate to high swim risk in place into this evening.

Low pressure over the Lower Great Lakes will steadily shift off to
the east of the U.P. tonight through Monday afternoon. At the same
time, dry high pressure will build into the western half of the U.P.
tonight and then across all of the Upper Peninsula for Monday. There
may be continued cloud cover and a few rain showers in the evening
over the eastern U.P.; however, the trend will be for this to
diminish through the overnight hours. Otherwise, temperatures will
be cool tonight over the west half as skies clear, with temperatures
dropping well into the 40s. The east half may stay generally in the
50s with the clouds lingering through the early overnight hours.
Sunday, temperatures will warm into the 70s under mostly sunny skies
with fairly light winds.

.LONG TERM...(Monday night through Sunday)
Issued at 241 PM EDT SUN JUL 23 2017

Nam shows a trough over the lower Great Lakes 00z Tue with a ridge
over the southern Rockies and a trough on the west coast and also
across south central Canada. There is also a shortwave ridge over
the Red River Valley of the North into Manitoba and western Ontario.
This shortwave ridge moves into the upper Great Lakes on Tue with
troughing moving in by late Tue and this trough remains over the
area into Wed. Nam brings in some deeper moisture and 850-500 mb q-
vector convergence Tue night into Wed. Overall, did not make too
many changes to the going forecast and look fairly dry for the first
part of the forecast.

In the extended, GFS and ECMWF show a 500 mb ridge across the
southern U.S. with a trough over the Great Lakes region 12z Thu and
this pattern stays through Fri. The pattern amplifies Fri night and
Sat with the trough digging into the ern U.S. and the ridge
amplifying into the Rockies. A shortwave moves over the top of the
ridge and moves through the upper Great Lakes on Sun. Temperatures
look to be near normal for this forecast period along with fairly
dry weather.
&&

.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
Issued at 147 PM EDT SUN JUL 23 2017

Low level moisture across the area this afternoon into early this
evening will slowly exit to the south and east of the U.P. This will
allow IFR to LIFR celings to slowly improve through the early
evening hours from northwest to southeast. KCMX may see MVFR to VFR
ceilings late this afternoon into the evening hours. KIWD will take
a bit longer to see the drier air move in so the MVFR to VFR
conditions may hold of until early evening. KSAW will likely see
lower ceilings and visibility hang on the longest with upslope
northeasterly flow into the TAF site. It may be tough to clear out
by late evening for KSAW. If skies clear as expected over the
western TAF sites, KIWD and KCMX, then radiational cooling will be
substantial enought to allow fog to form as high pressure builds
over the area. This may lead to another round of IFR to LIFR
condtions for those TAF site. Not out of the question that KSAW
could see some lower visibility tonight, even with lingering cloud
cover, as the continued upslope flow remains in place, yet slowly
decreasing.
&&

.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 244 PM EDT SUN JUL 23 2017

North to northeast winds gusting 20 knots will gradually diminish
tonight into Monday as high pressure moves across the area and the
pressure gradient weakens. The next chance for stronger winds from
the south to southwest over 20 kts will be Tuesday afternoon into
Wednesday morning over eastern sections as a low pressure trough
crosses the region. Otherwise, winds this week will be 20 kts or
less.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
  Beach Hazards Statement until 8 PM EDT this evening for MIZ005-
     006.

Lake Superior...
None.
Lake Michigan...
None.
&&

$$

SHORT TERM...KEC
LONG TERM...07
AVIATION...KEC
MARINE...KEC