Centennial Heights, Michigan Weather Forecast Discussion

247
FXUS63 KMQT 181107
AFDMQT
Area Forecast Discussion
National Weather Service Marquette MI
707 AM EDT Thu Sep 18 2025
.KEY MESSAGES...
- Isolated to scattered showers and thunderstorms possible today
  and Friday across western Upper Michigan.
- Seasonable temperatures through the weekend.
- Rain and thunderstorm chances exist through early next week.
&&
.DISCUSSION...
Issued at 248 AM EDT Thu Sep 18 2025
Mid to upper level ridging is currently observed stretching north
into the Upper Great Lakes with an area of broad troughing and two
closed lows upstream across the Northern Plains per RAP analysis and
GOES Water Vapor imagery. Multiple shortwaves are noted rotating
around this area, including one lifting through northern Minnesota,
which helped focus shower/thunderstorm activity along a passing cold
front this afternoon and evening. Mild and moist air lingers
overhead otherwise, with widespread 50 and 60 degree temperature and
dewpoints. As the night progresses, northerly flow already being
observed will advect in a cooler airmass, which will help more
locations fall into the 50s. This cooling will likely result in fog
developing, which may be dense in some locations for the morning
commute.
Any fog should mix out this morning, followed by mostly cloudy skies
parking over most of the region. The 2 upstream upper level lows
will consolidate into a single closed upper level low through the
day, then take on a negative tilt as it slowly shifts eastward
Friday. 0z guidance suggests this will lift 2 shortwaves through the
region, one today and another late Friday. Both may support showers,
maybe some thunderstorms, mainly across the west half.  Temperatures
today will be cooler then the past few days, with most Lake Superior
lakeshore communities and the Keweenaw Peninsula topping out near
60F while the south half climbs to near 70F. Tonight, most should
fall to near 50F, save the lakeshores which may only fall into the
low to mid 50s. More widespread 60s are expected Friday.
Saturday into Monday, the now negatively tilted mid-upper level
trough will send waves of precip through the region as the trough
slowly moves through the Great Lakes. Early next week, a deep wave
looks to dive southeast into the Central Plains, then slowly shift
eastward through the week. How far south the wave dives is the main
question, as its possible the preceding system over our area could
linger into Tuesday, which may push the feature into the into the
southern Plains, as suggested by the 12z and 0z EC deterministic.
Overall, the potential for another closed low in the Great Lakes
next week will keep the chance for precipitation in the forecast.
&&
.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/...
Issued at 707 AM EDT Thu Sep 18 2025
Generally VFR conditions are expected across the TAF sites today and
tonight. However, there are a few exceptions. First, IWD could see
degradation down to MVFR with a few showers and storms potentially
impacting the site late this morning and again this evening. Second,
SAW may see some lowered vis and cigs this morning due to a fog bank
rolling into the area; while the impacts are up in the air at this
point given that the sun will erode fog at the sfc, thinking the
bank will bring MVFR to IFR cigs late this morning into early this
afternoon before going away by the mid-afternoon hours. While we
could see some patches of fog dropping vis below VFR early this
morning, with observations at SAW already showing improvements to
P6SM, thinking we are much more likely (80%+) to stay at 6SM or
above for the rest of the daylight hours today. For the final
exception, it appears that patchy fog could return to SAW late
tonight; lowered vis down to MVFR late tonight since model and LAMP
guidance hints at this solution.
&&
.MARINE...
Issued at 248 AM EDT Thu Sep 18 2025
Northeasterly winds over the lake will continue into tonight, then
become more easterly Friday. Over the west half of the lake,
northeast winds will strengthen to near 25 knots today and up to 30
knots on Friday west of the Keweenaw Peninsula. Over the east half
winds will generally be below 20 knots. Patchy fog will also be
possible over the far eastern part of the lake tonight as the
cooler, moist air moves into the area. Winds become southeasterly
Friday night and increase to 20-25kts over the east half while the
west stays below 20kts. Winds may lighten through the day some, with
near 20kt winds lingering over the east half into early Sunday. From
there, winds mostly below 20kts are expected.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
  Dense Fog Advisory until 9 AM EDT this morning for MIZ007-085.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
DISCUSSION...JTP
AVIATION...TAP
MARINE...JTP

NWS MQT Office Area Forecast Discussion