Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Cleveland Ohio
300 PM EST Friday Feb 5 2016
high pressure will move southeast of the area tonight as low
pressure moves across the northern Great Lakes to eastern Ontario.
The low will move into Quebec Saturday. Sunday a clipper system
will move into the northern plains and upper Midwest. Monday the
system will move across Michigan and into Ohio.
Near term /through tonight/...
high pressure in place across the area will drift southeast
overnight. Satellite shows clouds across Michigan and into
northern Indiana in an area of weak isentropic lift ahead of a
weak trough. The NAM also shows a short wave in the general area
as well. Following 850mb moisture which is a good proxy so
far...this moisture moves east across the area through the night.
Will use the nam12 850mb relative humidity as a starting template for sky cover
grids tonight. The hrrr brings in some patchy flurries but for
now will leave dry. Will go within a few degrees of mav temperature
guidance for tonight.
Short term /Saturday through Sunday night/... Saturday morning
the weak trough exits to the east in the morning as another weak
upper trough drop toward the area. Also a surface low moves across
southeastern Canada north of the region. Best moisture remains north of
the area closer to this system so am expecting at least partly
sunny conditions for the day with highs around 40. Saturday night
we should see weak warm advection across the region as the cold
front from the Canadian low stalls across the Central Lakes.
Sunday another low will move across Minnesota into Wisconsin from
scntrl Canada. This clipper system will move into the area Monday
and should bring rain changing to snow beginning Sunday night.
Will have chance probability of precipitation in the west to begin with but after midnight
will move chance probability of precipitation east and increase to likely west. Highs
above normal Saturday and Sunday.
Long term /Monday through Friday/...
winter will be returning for next week with several chances for area
wide snow showers and colder temperatures. Closed upper low will be
making its way from the upper Midwest and to the upper Ohio Valley
between Monday and Tuesday. Temperatures Monday may be
marginal...and we may see a rain/snow mix. It will get cold enough by
Monday night for all snow. By Tuesday night the precipitation looks to be
confined more to the snowbelt as high pressure begins to build
across the western Great Lakes. The western ridge/eastern trough
will remain through the end of the week as the upper low reorganizes
itself around James Bay. By the end of the work week we start to see
some spread in the degree of cold air across the Great Lakes...with
the GFS the coldest.
Aviation /18z Friday through Wednesday/...
last bit of MVFR ceilings across far NE Ohio/northwest PA will lift to VFR
over the next few hours. Beyond that expecting all taf sites to be
VFR through 18z Sat. There will be a weak trough that crosses the
area tonight with a middle ceiling between bkn035 and bkn050. Tol
would likely have the only real chance at an MVFR ceiling for a
time tonight. Winds will be under 12 knots and generally from the
Outlook...non VFR likely Sunday night through Wednesday.
light southwest flow will continue tonight...but will increase on
Saturday to 15 to 20 knots as a clipper brushes the Great Lakes.
Between Sunday and Monday the winds will come around to the
southeast and begin to decrease in response to low pressure
approaching from western Superior. This low will stall and remain
across the eastern lakes through Tuesday. West-northwest winds
increase Tuesday night and continue to be strong through Wednesday
as colder air arrives. During this period 20 to 25 knots look common.