Weather

427 
fxus61 kcle 280602 
afdcle 


Area forecast discussion 
National Weather Service Cleveland Ohio 
202 am EDT Thursday Aug 28 2008 


Synopsis... 
the remnants of Fay will continue to move northeast through the 
eastern Ohio Valley region and then dissipate by Thursday morning. 
A high pressure ridge will continue to dominate the region from 
the northeastern United States into Pennsylvania and Ohio Thursday 
through Friday morning. Low pressure will move east across the 
southern Great Lakes region and force a cold front east through 
the forecast area on Friday. High pressure will build east across 
the region into the Holiday weekend. 


&& 


Near term /until 6 am this morning/... 
increased the rain chance wording east. 


Previous...precipitation associated with Fay will continue to 
lift to the north. The areal extent of the precipitation will 
continue to decrease through the night as the activity collides 
with drier air over the region. Positive vorticity advection 
moving north with the activity will move well north of the region 
this evening. The precipitation is expected to be confined to the 
eastern third of the forecast area while the western two thirds 
remains for the most part dry. 


More vorticity advection is expected later tonight and this may help 
to support more shower activity through the entire night. I am going 
to drop back probability of precipitation for the tonight period and go with scattered 
showers all night long over the eastern third of the forecast area. 
Satellite indicates a fairly large area of cloud cover moving north 
so will continue with cloudy skies all areas. 


Temperatures will once again be a tough forecast through the night. 
Highs so far have not even climbed out of the 60s in the east while 
they were around 80 in the west. I decided that since cloud cover 
would be present...temperatures will not drop too much through the 
night. Will go with lows generally in the upper 50s to around 60 
degrees across the area. 


&& 


Short term /6 am this morning through Saturday night/... 
Fay dissipates tomorrow morning and residual tropical atmosphere 
will be leftover just in time for the next cold front to move 
through the region on Friday. Ridge will build back southwest into 
the forecast area late Thursday afternoon into the evening hours. 
Most of the forecast area should remain dry. Some lingering slight 
chance type shower activity will linger in the east. 


Cold front approaches Thursday night from the west and this feature 
will bring a chance again for some showers and thunderstorms as 
instability increases with day time heating. 


Front is expected to move west to east on Friday and models are not 
too excited on precipitation quantity. I think this is going to be 
a situation where thunderstorms develop and produce some locally 
brief heavy rain in a short period with lingering low level moisture 
in place. Some locations may get a good dump of rain and other 
areas could possibly escape with a quick shower that amounts to very 
little rainfall. 


Front clears the area quickly Friday night bringing an end to the 
precipitation threat. High pressure builds east over the weekend 
and this should set the stage for a dry Holiday weekend with plenty 
of sunshine and dry air in place. 


Temperatures through this period will warm once again ahead of the 
cold front and then settle back down slightly on Friday after 
frontal passage. Warm air advection is expected to return Saturday 
night as high moves to the east and southerly flow develops. 


&& 


Long term /Sunday through Wednesday/... 
surface and upper level high pressure should control the weather 
Sunday through Wednesday. May see a trough approach the western County 
Warning Area for the middle of next week but will not mention 
yet. Otherwise expect dry conditions with temperatures at or above 
seasonal averages. 


&& 


Aviation /06z Thursday through Monday/... 
remnants of Fay continue to impact the area this morning. Rain 
confined more to eastern sites this morning. For tafs...quite a 
variation from west to east forecast wise. For tol and fdy this 
morning went with predominate MVFR with some tempo IFR. 
However...expecting western sites to be quite variable over the 
next 6-8 hours with sites at times bouncing around with scattered low 
ceilings at times. Despite that...went with mainly MVFR with IFR 
conditions at times. Guidance showing out west ceilings will 
continue to remain low through much of the day...but clear skies 
less than 50 miles away to the west thinking that time of year 
will allow ceilings to slowly dissipate especially after 18z. 


Forecast becomes trickier further east. For mfd do not see reason 
for improvement at mfd with better probability of conditions 
deteriorating even further towards daybreak. Trended in same 
directions at cak. Cle is a bit more difficult with downsloping southeast 
wind being more of an influence. With that mentioned predominate 
IFR towards daybreak expecting winds to be a bit more easterly...but 
then broke out into low MVFR shortly after about 14z with winds 
shifting a bit more southeast. For yng downsloping has helped things 
there until most recently...but see little room for improvement 
through much of the day today not until late. Southeast flow to prevail 
there allowing MVFR conditions to be somewhat difficult to come 
by. With that only mention MVFR through morning hours...then 
improving in afternoon. 


Outlook...any improvement to VFR late this evening in west will be 
short lived with MVFR returning. Eastern sites except eri 
continuing mainly MVFR with patchy VFR improvements. Possible MVFR 
Friday with cold front and br Friday night. VFR Sat through Monday. 


&& 


Marine... 
things remain fairly quiet on the lake as compared to the past few 
days. Easterly flow continues but is expected to become more southeast the 
next few hours as the remnants of Fay move toward Ohio. This low 
is expected to dissipate as it approaches the east end of the lake 
on Thursday. Southeast flow will continue on the lake till Friday am when south 
winds will develop. A cold front is still on track to cross the 
lake on Friday. Some showers and storms possible out ahead of this 
front. Winds on the lake will become northwest by the end of the day. It 
appears that waves and winds will remain just below small craft 
criteria. The northwest flow will continue into Saturday and then become 
light and variable as high pressure builds over Lake Erie for the 
remainder of the Holiday weekend. 


&& 


Cle watches/warnings/advisories... 
Ohio...none. 
PA...none. 
Marine...none. 


&& 


$$ 
Synopsis...Lombardy 
near term...tk/Lombardy 
short term...Lombardy 
long term...Mullen 
aviation...Abe 
marine...kubina 

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