Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Cleveland Ohio
122 am EDT Tuesday Sep 2 2014
a cold front will move east across the area on Tuesday. High
pressure will build north out of the Gulf Coast states Tuesday
through Thursday and then move to the East Coast. A warm front will
lift north across the region Thursday as low pressure moves east
across the northern lakes Thursday night. A cold front trailing from
the low will sag southeast over the region Friday night.
Near term /until 6 am this morning/...
showers and thunderstorms associated with the prefrontal trough
are located out over Lake Erie and are moving with an east-
northeast direction. Therefore they may clip Erie County PA before
heading off to New York. All others will be primarily dry although
cannot rule out a stray shower/ts overnight.
A cold front was located far to the west...near Chicago. The
better chance of precipitation comes much later tonight as a wave
develops along this front with support of an upper level wave and
jet maximum. A steadier rain with embedded thunder will begin to work
its way in from the Findlay area northeast toward morning. There
is some question as to how fast it can move into the area before 6
Area will still be in the warm sector overnight and expect lows
only in the upper 60s and lower 70s.
Short term /6 am this morning through Thursday night/...
morning shortwave will pull northeast and diminish the rain
chances as the day GOES on Tuesday. The biggest question is how
far north this area of rain tracks. Have Toledo in the chance
category...and the southeast third of the area in categorical
probability of precipitation. The cold front will cross the area during the day on
Tuesday...with improvement from west to east.
The broad upper level trough will begin to lift out of the area on
Tuesday allowing for zonal flow to develop from west to east
through this period.
High pressure will begin to build in from the Gulf Coast states and
bring drier air to the region. The high pressure will become the
dominating weather feature through Wednesday. A warm front will lift
northeast along with some limited mean 1000 to 500 mb moisture on
Thursday and we could see a minimal chance for showers and
thunderstorms by Thursday night. Will hold on to the slight chance
at this point since moisture will be so limited.
Air mass behind the cold front is not that strong so not expecting
too much in the way of cold air advection on Tuesday into Tuesday
night. Lows will drop off however about 10 degrees Tuesday night and
then begin to recover Wednesday and Wednesday night as warm air
advection begins to take place. Further warming takes place Thursday
and Thursday night in the earnest warm air advection. 850 mb
temperatures climb from 16c on Tuesday back to around 20c by
Long term /Friday through Monday/...
models in fair agreement today. Will start to see precipitation chances
increase on Friday as a moist southerly flow develops ahead of a
cold front. Friday night and Saturday will be wet and the likely
probability of precipitation in the previous forecast seem reasonable. The cold front will
move south across the area Saturday and precipitation should end during the
afternoon. There will be a distinct air mass change behind this
front with dew points dipping into the 40s and temperatures becoming
below normal. By Monday...morning lows will be in the 40s some areas
with highs struggling to get to 70. With high pressure overhead
there should be a lot of sunshine both Sunday and Monday.
Aviation /06z Tuesday through Saturday/...
weak cold front to our northwest with best guess position from
central lower Michigan SW into MO. Mesoscale convective system across MO and southern Illinois while a few
lingering showers along with a little thunder across far eastern
Erie County PA and east into western New York. That activity will continue
east out of the area over the next hour or two. Hrrr does show
some redevelopment over Erie County and will account for that in
the taf. Otherwise mainly VFR across the area this hours although
the hrrr does show activity to our west moving into the area
towards morning. Expect the bulk of the convection to remain south
of our area...tracking across central and southern Ohio...however so
expect some precipitation to extend north and affect the area. Brought
showers into ktol/kfdy around 10z and kcle/kmfd 11-12z and Keri-
kyng 14-15z. Also included thunderstorms in the vicinity but for now did not include thunder in
tempo groups. Held onto MVFR ceilings through the balance of the
morning given deep high relative humidity across the area. Drier air should begin
moving in through the afternoon.
Outlook...non VFR likely in showers and thunderstorms by Friday
evening into Saturday with the next cold front.
southwest to south flow will continue till a cold front crosses the
lake on Tuesday. It appears showers and thunderstorms will occur on
the lake this evening and again right ahead of the cold front early
Thursday. Some of the storms on the west end could be strong this
evening. Looks like speeds and waves will remain just below small
craft criteria tonight so will hold off on any issuance. The flow
will become westerly behind the front. High pressure will build
over the lake for the middle part of the week resulting in light and
variable flow. The surface ridge will eventually move off to the
east on Thursday allowing a weak southerly flow to develop. S to SW
flow will then gradually increase till a cold front crosses the lake