FXUS61 KCLE 220554
Area Forecast Discussion
National Weather Service Cleveland OH
1254 AM EST Sun Jan 22 2017
Temperatures will remain mild through Monday as low pressure
tracks from the Mississippi valley northeast towards the Mid
Atlantic states. A ridge of high pressure will build across the
region Tuesday into Wednesday. A low pressure system will track
east across the southern Great Lakes Wednesday with more
seasonable temperatures arriving late week.
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
Showers across the east and another batch over Indiana. There has
been some thunder so have added that mention to the forecast.
The thunder across Indiana likely associated with right rear
quadrant of 5h jet and warm frontal boundary around 8H.
.SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY NIGHT/...
Focus of the short term period is precipitation chances Sunday
through early Tuesday. Upper low will slowly track and deepen from
the lower Mississippi valley Sunday morning to the upper Ohio valley
by Monday afternoon in response to strong southern stream jet
energy. Models are in decent agreement with track/evolution of upper
low and attendant surface reflection. The precip arrival Sunday has
trended a bit slower, with much of the morning/earlier afternoon
possibly dry across the forecast area. Adjusted the forecast to
reflect this trend, with chance pops arriving after 17Z and likely
pops holding off until 21Z and after.
Best window for precipitation, and possible heavy rainfall, will be
Monday morning/early afternoon, especially across the eastern half
of the area where cat pops have been expanded a bit. This is where
best forcing will be present as the upper low tracks along the
Appalachians just east/southeast of the area. Kept QPF amounts Sunday
through Monday night ranging from 0.30" west to around an inch east.
Precip will wind down Monday night/Tuesday morning as the low tracks
eastward off the Atlantic coast. One wild card in the Monday night
time frame is p-type. ECMWF and GFS tend to be on the warmer side
with the low, with perhaps a brief period of changeover to rain/snow
mix late Monday night. The NAM, however, wraps much more colder air
into the low, with p-type changing over much earlier Monday evening,
and perhaps a changeover to all snow overnight, with some
accumulation possible. For now, discounted the NAM and went with a
GFS/ECMWF blend for column temperatures and resultant p-types, with
rain and snow mentioned Monday night. This solution will need to be
watched over the coming model runs and the forecast will be adjusted
High pressure ridge will build across the region Tuesday. This
should yield dry conditions much of Tuesday and Tuesday night.
Northern stream wave will track from the central Rockies toward the
Great Lakes, with precip arriving towards 12Z across the area. P-
types may be in issue, especially NE OH/NW PA high elevations, but
it is too early for specifics other than a cursory rain and snow
Temperature wise, went a few degrees warmer for highs on Sunday with
slower precip arrival trend, near MAV/EC MOS, but not as warm as MET
MOS. This yields upper 50s/mid 60s across much of the area.
Temperatures will trend cooler Monday through Tuesday, but still
well above seasonal normals.
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
The long term begins on Wednesday with models in good general
agreement showing an upper over the upper midwest and a general
southwest flow aloft over the area. At the surface, low pressure
will be in SERN MN with a warm front into western Ohio and a cold
front south from the low through Indiana. The low will move
northeast across the Great Lakes dragging both fronts across the
region during the day. Temps will fall behind the cold front
changing rain Wednesday into snow Wednesday night. Thursday 850mb
temps should be around -5C which should keep most precip snow during
the day. Continued with chance pops most places although did keep
likely northeast with flow off the lake for potential lake
enhancement although it would be minimal given temps. No big change
Friday although 850mb temps continue to slowly drop. Friday night
into saturday another trough rotates across the region bringing
colder air to the region with 850mb temps dropping to -10c and
likely continuing lake effect enhancement northeast.
.AVIATION /06Z Sunday THROUGH Thursday/...
Showers have filled in east of I-71 and continue to make slow
progress to the east and northeast. The models still show this
activity dissipating overnight. Already seeing some LIFR
conditions over northern Indiana. Have backed off some from
earlier forecasts but still expecting widespread MVFR cigs to
develop overnight with areas of IFR fog as well. VSBY's will
likely be the worst in the west. Will try to improve conditions
back to VFR on Sunday. The main show will start tomorrow evening.
Expect cigs to once again dip to back to MVFR by 00Z Monday. Rain
will spread north across the area tomorrow evening. Light
southerly flow will become easterly after 12z and northeast by the
end of the period.
OUTLOOK...Non-VFR developing Saturday night continuing into Monday
in rain. Non-VFR will likely persist on Tuesday across NE OH/NW PA.
Light south to southeast flow on the lake today through tonight as a
warm front lifts north of the lake. Flow will remain light Sunday as
it turns out of the northeast in response to low pressure moving
through the Tennessee valley. This northeast flow will increase
Sunday night reaching 15 to 20 knots overnight and 20 to 25 knots on
Monday before turning north and dropping back to 10 to 15 knots
overnight Monday night. Winds will increase again from the southwest
Wednesday to 15 to 25 knots as low pressure moves through the
central lakes. Would anticipate small craft headlines will be needed
early Monday into/through Monday night and late Wednesday into