Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Cleveland Ohio
1209 PM EST Thursday Nov 26 2015
a warm Thanksgiving on track for the area this afternoon. A
large area of high pressure spanning the entire East Coast will
gradually shift east today through Friday. A cold front is
expected to move east across the area Friday afternoon and early
evening. Low pressure will move slowly north up the Mississippi
Valley region to Minnesota by Monday night. A warm front from the
low will lift north across the area Monday night followed by a
cold front Tuesday.
Near term /until 6 PM this evening/...
satellite indicating some clearing of the clouds as the dynamics
over the area begin to wane. There remains a fair amount of clouds
upstream that will thin while moving into the area this afternoon.
Temperatures are on track to warm into the 60s with the
combination of warm air advection...sunshine...and downsloping
winds. The downsloping is also supporting some good mixing as we
are seeing wind gusts around 25 to 30 miles per hour.
Short term /6 PM this evening through Sunday night/...
the upper level ridge over the eastern Seaboard will break down
briefly as a broad trough moves east across southern Canada into the
northeast. This trough will allow the stationary front to become a
cold front and move gradually east across the area Friday afternoon
into Friday night. There are some timing differences with the GFS
model compared to the rest of the models. The GFS prognosticated the cold
front to move through the area around 18z Friday while all of the
other models suggest a 00z Saturday timing. Since the GFS is the
outlier will lean in the direction of the 00z timing.
Front swings through the area Friday afternoon into Friday night
bringing with it some showers. Eventually the cold front sags south
across the Tennessee Valley into the Carolinas by Saturday evening.
This should bring an end to the precipitation for a period of time.
Then...low pressure is expected to begin moving north up the
Mississippi Valley region and force a warm front north. The warm
front will bring with it another chance for showers into the
southwest portion of the forecast area by Monday morning.
Temperatures through the period will settle back down into the 50s
for highs on Friday and upper 30s for lows and then into the 40s for
highs by Saturday through Monday as cold air advection begins to
Long term /Monday through Wednesday/...
the big southwestern storm system is prognosticated to lift out early next
week. As would be expected with upper lows...there are still some
inconsistencies in the models but given the situation...there is
somewhat reasonable agreement.
The upper low is prognosticated to cross the upper Midwest Monday night and
Tuesday with the occluded front sweeping across the area roughly the
same time frame. Not sure how fast the precipitation will return from the
south/southwest on Monday. The GFS is the fastest on Monday while
the other models are slower... Monday night. My hunch is that the
ridge aloft combined with the dry surface high just to the east on
Monday may keep most of the area dry but we have low pop chance of
showers across Northwest Ohio on Monday and will continue with that
forecast given the uncertainty.
Better chance of showers pushing across the area Monday night and
Tuesday morning with the occluded front. We may not cool down
much on Tuesday with the dry slot and occluded air mass. Will
forecast highs still above normal...from the middle 40s to the lower
50s. The cooler air should certainly be here by Tuesday night and
Wednesday with lows/highs closer to normal and some wrap around
rain and snow showers. It may just get cold enough for a Little
Lake effect snow by Wednesday if we can get a favorable wind
Aviation /12z Thursday through Monday/...
south winds will continue to gust around 25 knots periodically
through the next 24 hours. Low level wind shear a concern
especially for western sites with a strong low level jet overhead.
The low level wind shear will be maximized late tonight and early Friday morning.
VFR conditions will continue with variable middle clouds. Cold front
will be across Northwest Ohio around 18z Friday. There is some timing
differences on when the rain starts. Have aligned the non VFR
conditions with the arrival of the rain.
Outlook...non VFR developing Friday afternoon and continuing into
Saturday. Increasing chances of non VFR again Monday.
there is a decent low level south jet today into Friday and some
of that wind is finding the surface over the east half of Lake
Erie. Winds on the east half of the lake will reach 25
knots...perhaps 30 knots... for a while this morning. The wind
will likely drop off a bit this afternoon...then pick right back
up tonight into Friday. Will not try to split the Small Craft
Advisory since winds/waves will remain near the advisory criteria this
afternoon even during the short lull. Will extend the Small Craft
Advisory into Friday.
The remainder of the lake will see sustained south winds between
10 and 20 knots into Friday. The lake will be choppy today
especially in the open waters.
The cold front will cross the area Friday afternoon and winds will
shift to the northwest and north and will likely be strong enough
for a Small Craft Advisory later Friday night into Saturday.
High pressure will cross the Great Lakes Sunday and the wind and
waves should diminish although the northeast fetch may keep the Lake
A bit stirred up.
Marine...Small Craft Advisory until 4 PM EST Friday for lez148-149.