Lucas and Wood Counties
fxus61 kcle 190148
area forecast discussion
national weather service cleveland oh
948 pm edt fri sep 18 2020
a high pressure center moves from the upper great lakes to southern
quebec and strengthens through this weekend. simultaneously, the
associated ridge affects our region.
.near term /through saturday night/...
westerly flow aloft becomes progressively northwesterly over our cwa
through the period. simultaneously, a longwave trough over eastern
canada, the great lakes, and the northeast united states moves
eastward very slowly as a longwave ridge builds from the west. at
the surface, a ridge affects our region as the embedded high
pressure center moves from the upper great lakes to southern quebec.
fair weather is expected through the period.
skies should trend mainly clear through the period. however, as
a cold low-level flow crosses lake erie, lake effect stratocumuli
will stream south-southwestward from the lake through this
early evening and then southwestward overnight tonight into
saturday morning. limited or no lake effect cloud cover is
expected saturday afternoon through saturday night as subsidence
strengthens over our area. no precip is forecast to accompany
the lake effect clouds since limited moisture and sizable
directional shear in the low-levels should allow dry air
entrainment to curb lake-induced instability.
tonight will be chilly, with low temperatures reaching the 30`s in
many locations inland from lake erie. patchy frost may develop where
low temperatures reach the mid 30`s around daybreak. however, more
widespread frost is expected to form in southern erie and crawford
counties in pa, and in southern ashtabula, trumbull, and mahoning
counties in northeast oh. widespread lows in the lower to mid 30`s
are expected in these areas and a frost advisory is in effect from
12 am to 9 am edt saturday morning. relatively-warmer low
temperatures in the 40`s are expected along and very near the lake
below-normal afternoon high temperatures in the upper 50`s to mid
60`s are expected on saturday. saturday night should be colder as
very light or calm surface winds contribute to efficient radiational
cooling. widespread low temperatures in the 30`s are expected inland
from lake erie, which should be accompanied by more extensive frost
formation. additional frost-related headlines will likely be needed.
somewhat warmer low temperatures in the lower to mid 40`s are
expected along and very near the lake erie shore.
.short term /sunday through monday night/...
high pressure will persist over the area through the short term
period. the only concern during this forecast period is for the
possibility of frost headlines overnight sunday and monday.
currently, forecasted overnight lows drop down into the mid to upper
30s, with the lowest temperatures focused in northeastern ohio and
northwestern pennsylvania. with the high pressure in place, mainly
clear skies may lead to temperatures being slightly cooler than
currently forecasted based on guidance. these temperatures will need
to continue to be monitored as they move into the near term forecast
period. currently, the best chance for frost remains across
northeast ohio and inland areas of northwest pennsylvania.
.long term /tuesday through friday/...
the long term forecast will continue to remain quiet as the high
pressure remains over the area through wednesday. temperatures will
remain cool on tuesday with highs in the high 60s to low 70s. as the
high pressure moves off the east coast, warm air advection will
increase over the area as winds become southwesterly on wednesday
and temperatures will again begin to increase. high temperatures on
wednesday will be in low to mid 70s. on thursday, an upper level
trough and surface cold front will move across the area, although it
is uncertain how much moisture will be present over the area. the
amount of moisture will be the deciding factor if the area gets any
appreciable precipitation. for now, opted to keep chance pops for
thursday afternoon and evening, although models are trending with
the trough keeping the front just north of lake erie.
.aviation /00z saturday through wednesday/...
surface high pressure continues building in from the northwest,
currently centered over michigan. the surface high pressure will
be centered over southern ontario by tomorrow afternoon.
scattered lake effect clouds are expected to continue streaming
south-southwestward from lake erie early tonight before
becoming more southwest overnight and through the day saturday.
occasional mvfr ceilings may accompany the lake effect clouds,
which could impact kcle, keri, and ktol. cloud cover dissipates
by saturday evening.
outlook...non-vfr in patchy fog possible around daybreak and
inland from lake erie sunday through tuesday.
current marine headlines will persist through early tomorrow morning
for portions of the central basin as northeasterly winds persist at
20 to 25 knots creating waves 3 to 6 feet. by saturday morning,
winds will shift to more easterly and weaken to 10 to 15 knots and
are expected to persist through sunday. winds will then begin to
veer on monday and become southwesterly by tuesday, remaining at 10
to 15 knots. there are no additional marine headlines anticipated in
oh...beach hazards statement until 4 am edt saturday for ohz009>012.
frost advisory until 9 am edt saturday for ohz014-023-033.
pa...frost advisory until 9 am edt saturday for paz002-003.
marine...small craft advisory until 4 am edt saturday for lez144>147.
Fulton and Henry Counties
fxus63 kiwx 182226 cca
area forecast discussion...corrected
national weather service northern indiana
625 pm edt fri sep 18 2020
issued at 251 pm edt fri sep 18 2020
a period of cooler temperatures is expected tonight and saturday
with the possibility of frost forming by early saturday. high
temperatures will start the period on saturday in the low 60s, but
trend warmer eventually reaching the upper 70s to near 80 on
wednesday. also expect a dry forecast through next week.
.short term...(this evening through saturday)
issued at 251 pm edt fri sep 18 2020
high pressure on the back end of the trough continues to keep the
area dry for this period. a strong subsidence inversion is forecast
to form tonight as indicated by bufkit soundings. dewpoints are
expected to drop into the low to mid 30s across much of the area
tonight while winds slow down to around 5 kts. winds out of the east
could help to keep areas east of i-69 and south of us-6 a little
warmer on some lake erie marine air as indicated by the low level
theta-e gradient in that area on the nam model. with all of this in
place, expect temperatures to fall into the upper 30s. as such a
frost advisory has been issued for saturday morning. the best chance
for frost will be in areas west of i-69 though where the coolest
temperatures and lightest winds are forecast to reside, but can`t
rule it out in nw oh either. be sure to cover very sensitive
plants in the advisory area.
after the cool morning temperatures, mixing heights to between 900
and 850 mb where 3 to 5c temperatures reside allow for low to mid
60s for high temperatures under skies with little if any clouds on
saturday. these temperatures of low to mid 60s for highs and mid
to upper 30s for lows is more typical for october so these are
below average temperatures for this time of year.
.long term...(saturday night through friday)
issued at 251 pm edt fri sep 18 2020
the long term will be characterized by a departing trough early in
the period and a strengthening ridge over the western half of the
conus into western areas of the great lakes region during the rest
of the period. some tropical activity in the gulf moves ashore, but
will be swept east before they can affect the area with tropical
moisture. as such the area will continue to remain dry; even
thursday as the cold front that swings through is rather devoid of
moisture. also, a warming trend is expected from saturday to
wednesday becoming more seasonable to slightly above normal ahead of
thursday`s cold front.
.aviation...(for the 00z tafs through 00z saturday evening)
issued at 625 pm edt fri sep 18 2020
tremendous sfc ridge slowly transecting the lakes this period
assures vfr with nil wx.
in...frost advisory from 2 am edt /1 am cdt/ to 9 am edt /8 am cdt/
saturday for inz003>009-012>018-020-022>027-032>034.
mi...frost advisory from 2 am to 9 am edt saturday for miz077>081.
oh...frost advisory from 2 am to 9 am edt saturday for ohz001-002-004-
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Monroe and Lenawee Counties
fxus63 kdtx 190000
area forecast discussion
national weather service detroit/pontiac mi
800 pm edt fri sep 18 2020
daytime cumulus has dissipated this evening with mostly clear skies
taking over through tonight. the only exception will be some passing
cirrus coming in from the northwest. high pressure drifting east
through the central great lakes will bring light northeasterly winds
which will begin to back out of the southeast throughout the day
tomorrow as the high pressure drifts east of the state. daytime
cumulus will become harder to come by tomorrow with drier air in
place and lake moisture becoming less influential, but it remains
possible that some few-sct cumulus could develop again around 5kft.
winds will remain weak at around 5 knots.
.dtw threshold probabilities...
issued at 354 pm edt fri sep 18 2020
center of surface high pressure is centered over the portions of
lake michigan and northern lower michigan this afternoon. the
surface high has broad support from upper level confluent flow and
deep 950-550mb anticyclonic flow trajectories. main discussion point
for tonight will be on frost potential. ideal radiative cooling
conditions will develop tonight as surface decoupling occurs and
winds trend variable this evening. with surface dewpoints currently
running in the low to mid 30s and moist/green up conditions lows
tonight should remain buoyed in the lower to middle 30s across the
area. a few isolated interior locations across northern saginaw
valley may drop into the upper 20s. issued a frost advisory for the
entire cwa from midnight tonight through 9 am saturday
the main narrative throughout this upcoming weekend will be ideal,
dry, early autumn weather for southeast michigan. previous
discussion referenced low pwats throughout the entire weekend.
surface dewpoints will run in the 30s and 40s. temperatures this
weekend will be some 5 to 10 degrees below normal.
dry conditions are expected to persist through the early to middle
of next week. there is model signal the longwave will become
increasingly more amplified next week. the central great lakes
appear to be in a favorable position to experience a zonal flow
inflection point within the longwave. this is important as it
suggests a continued dry southwesterly trajectory. expecting some
movement on high temperatures for next week as current automated
values appear to be washed out. suspect high temperatures will be
warmer on a few days next week compared to what is currently being
onshore flow will persist through this afternoon as winds begin to
diminish through the early evening with conditions falling below
small craft criteria. high pressure will continue to build in from
the west and will move directly over the central great lakes and
bring more favorable boating conditions over the weekend with light
and variable winds and low wave action.
mi...frost advisory from midnight tonight to 9 am edt saturday for
lake st clair...none.
michigan waters of lake erie...none.
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The three regional National Weather Service offices that cover the Toledo area include Cleveland, Detroit/Pontiac, and Northern Indiana.