903
FXUS63 KMQT 142323
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
723 PM EDT Tue May 14 2024

.KEY MESSAGES...

- Quiet and dry weather with borderline elevated fire weather
  conditions continues through Wednesday
- Scattered showers and a few embedded thunderstorms are
  possible Thursday and again on Saturday.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 143 PM EDT Tue May 14 2024

Upper air pattern consists of a 500 mb closed in Missouri and a
shortwave in the northern Rockies. The shortwave moves east into the
northern plains by 12z Wed. Quiet and dry weather will continue
through tonight and did not make too many changes to the going
forecast.

&&

.LONG TERM /WEDNESDAY THROUGH TUESDAY/...
Issued at 526 PM EDT Tue May 14 2024

The main story of the long term period is the transition from dry
conditions and fire wx concerns to a period of unsettled weather.
It`s important to note that even though rain chances become more
common, most places will be dry most of the time associated with
isolated rain showers instead of steady rain. These showers appear
to be primarily forced by a frontal boundary that wavers back and
forth across the area with each passing disturbance and forecaster
confidence diminishes quickly after Thursday night. A few embedded
thunderstorms cant be ruled out with each disturbance, but probably
just generic thunderstorms without severe potential. Otherwise,
temperatures trend above normal with Fri-Sun looking like prime
spring weather with highs mainly in the 70s and lows in the 40s to
around 50F.

Starting with Wednesday, mostly sunny skies should warm temps well
into the 60s across most of the UP with 50s immediately downwind of
Lake Superior. Model soundings suggest poor nocturnal RH recovery
tonight and we mix into a very dry mid-level layer on Wednesday.
Despite increasing upper level clouds I`m reasonably confident that
tomorrow`s min RH values will be lower than today due to dry
easterly flow downsloping off the Canadian Shield. This dry air mass
persists until a warm front lifts across the area on Thursday. This
suggests another night with poor RH recovery, especially across the
west where downsloping southeast winds keep the boundary layer well-
mixed. Model guidance continues to trend slower with these rain
chances and I have largely removed PoPs from Wednesday night and
they don`t reach the far east until Thursday evening/night. Given
the model trend and antecedent dry air mass, I`m pessimistic about
rainfall amounts even though there are some hints at weak CAPE. The
current forecast calls for generally less than 0.1" of rain by
Friday morning and that seems reasonable.

Despite diminishing forecaster confidence, there seems to be good
agreement that lingering rain showers exit stage right Friday
morning with a dry stretch continuing into Saturday. On Saturday
morning, a sub-1000 mb surface low will be positioned near Lake
Winnipeg that occludes while tracking east across northwestern
Ontario by Saturday night. This system sends a warm front across
the area Saturday morning leading to our warmest day of the
extended period with interior locations possibly warming into
the 80s. It`s unclear when the systems cool front moves across
our area, but that feature likely represents the next rain
chance. If it ends up moving through during the afternoon and
evening then the probability of embedded thunderstorms
increases. This front should clear the area Sunday morning
leading to another dry stretch. EPS guidance suggests
cyclogenesis along the remnant boundary over the Central Plains
early next week that may track northeast into the Great Lakes
region.

&&

.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 722 PM EDT Tue May 14 2024

VFR conditions will prevail for the duration of the TAF period.

&&

.MARINE...
Issued at 526 PM EDT Tue May 14 2024

Light winds of generally 20 knots or less continue into Wednesday as
surface ridging persists across Lake Superior. However, a weak low
pressure tracks from the Northern Plains across the Upper Great
Lakes on Thursday. Northeast winds increase up to 25 kts across the
far western lake Wednesday through Thursday afternoon as this low
pressure approaches. As the low pressure tracks across the lake
Thursday, expect southeast winds to increase to around 20 kts across
the central lake with light winds below 20 knots return Thursday
night behind the low pressure. Light winds persist into the weekend.
There is a slight chance (~15%) for a few rumbles of thunder on
Thursday and perhaps again Saturday or Saturday night.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.

&&

$$

SHORT TERM...07
LONG TERM...EK
AVIATION...TDUD
MARINE...EK