420 
FXUS63 KMQT 272036
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
436 PM EDT Thu May 27 2021

.SHORT TERM...(This evening through Friday)
Issued at 246 PM EDT THU MAY 27 2021

High clouds associated with a low moving from the Central Plains 
into the Ohio Valley filled in the skies across the region. Overall, 
temps have been in the 40s, with the exception being close to Lake 
Superior, where a late morning burst of colder air off the lake 
filtered into the lakeshore. When this occurred, our office dropped 
about 3 degrees in an hour. 

This afternoon and tonight, a broad area of high pressure over 
Manitoba and Ontario and its ridge over our region should largely 
keep precip associated with this low to our south. The exception 
looks to be parts of southern Menominee County where precip could 
just clip it. P-type, believe it or not, is a little interesting.
Wetbulb zero heights suggest some snow may mix in with any rain. 
These chillier temps won't be isolated. In fact, much of the 
forecast area away from the lakeshores will see temps near or 
below freezing. Parts of the interior west could dip into the 20s.
Confidence isn't high on how low temps will fall given the high 
cloud cover that's expected to linger, but decided to go ahead and
issue a frost advisory for much of the central and western 
counties. Given the lakeshores only bottom out in the mid 30s, I 
don't expect frost to reach the lakeshores.

Tomorrow, the high will have shifted east some to Hudson Bay. With 
this, deep mixing will allow dry air to filter down to the surface. 
With temps progged to climb into the upper 50s away from Lake 
Superior, RH values will sink to near 20-25%. By the the lakeshores, 
where the lakes will help moderate things, RH values should bottom 
out in the 40%s. With breezier wind gusts near 20 mph being 
possible, fire weather could be a concern, particularly in areas 
that haven't seen much rain in a while.

.LONG TERM...(Friday night through Thursday)
Issued at 434 PM EDT THU MAY 27 2021

Models suggest that a progressive but mainly dry pattern will 
prevail into next week. A mid/upper level trough into the northwest 
CONUS will lose amplitude as it slides toward the Great Lakes early 
next week. A building ridge over the western CONUS will favor 
downstream troughing over the central CONUS toward the middle and 
end of the week. Temperatures will rebound closer to seasonal 
averages this weekend and remain at or slightly above normal through 
most of next week. 

Friday night, mid level and sfc ridging building and very dry air 
(PWAT to near 0.20 inch) building into the area will bring favorable 
radiational cooling conditions. Min temps into the mid 20s are 
likely over the interior west and into the lower 30s over the east. 
Even locations along the Great Lakes may also see some frost.

Saturday, plenty of sunshine with mixing to around 5k ft will boost 
temps into the mid and upper 60s (except 50s near the Great Lakes) 
and drop dewpoints at least into the low/mid 20s inland. This will 
drop RH values to around 20 percent. However, generally light winds 
below 10 mph will limit fire weather concerns. 

Saturday night and Sunday, some patchy frost may again be possible 
with light winds overnight and the dry airmass in place. As the 
sfc ridge moves off to the east, high temps in the upper 60s are 
expected, except along Lake Michigan. RH values again into the 
20-30 pct range with winds gusting to 15-20 mph over the east half
will likely result in an elevated wildfire weather risk.

Mon, an approaching mid level trough and sfc cold front with 
increasing low level moisture will bring the potential for at least 
sct showers. A thunderstorm may also be possible, but instability 
will be limited with dewpoints barely approaching 50F. 

Tue-Thu, additional pcpn chances seem minimal as the more favorable 
moisture remains well to the south with the southern stream portion 
of the developing trough. Models have trended away from any 
significant phasing as depicted by the GFS and some ensemble 
members. Some diurnal shra/tsra cannot be ruled out but more 
widespread or heavier showers are not expected. 

&&

.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
Issued at 133 PM EDT THU MAY 27 2021

VFR conditions are primarily expected to prevail through this TAF 
period. The exception being early in the period, where at KSAW 
onshore and upslope flow has been responsible for MVFR ceilings. 
Guidance suggests these should lift by mid-afternoon. Tomorrow, high 
clouds are expected to thin and deep mixing will allow for gusty to 
near 20kts winds to mix down to the terminals at KCMX and KSAW.
&&

.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 246 PM EDT THU MAY 27 2021

Northeasterly wind gusts to 25 knots this afternoon over the western 
portion of the lake will gradually improve and are expected to drop 
below 20 knots by this evening. These lighter winds are expected to 
persist over the lake into next week.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
  Frost Advisory from 1 AM EDT /midnight CDT/ to 8 AM EDT /7 AM 
     CDT/ Friday for MIZ002>006-009>011-013-084.

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

$$

SHORT TERM...JP
LONG TERM...JLB
AVIATION...JP
MARINE...JP