Weather

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fxus63 kdtx 110739 
afddtx 


Area forecast discussion 
National Weather Service Detroit/Pontiac Michigan 
339 am EDT Sat Oct 11 2008 


Short term...today 


A large high pressure system across the eastern Great Lakes will 
move eastward into Quebec by this afternoon. As the high moves off 
to the east...southeast winds will pick up as the pressure gradient 
tightens up with a developing low pressure system across the 
Southern Plains. Some high clouds may move through the area 
today...however abundant sunshine and well above normal temperatures 
are expected across the region today. MOS temperatures are 
relatively close...with cooler temperatures expected near lakes Erie 
and Huron with a southeast wind bringing cooler lake air to these 
locations. 


&& 


Long term...tonight through Friday 


Very little change made to the forecast for the Holiday weekend. 
Strong upper ridge will reside over the eastern half of the country 
through Monday...while a large trough deepens over the west. This 
will continue to provide unseasonably warm and tranquil Fall weather 
for Southeast Michigan Sunday and Monday. Rising thickness values 
and h850 temperatures near 16 degrees c support surface temperatures in the 
upper 70s to around 80 both days. Clouds and winds will start to 
increase on Monday however as lead energy ejecting out of the 
western trough lifts up into Canada. 


There is some uncertainty with how the western trough will evolve as 
it crosses The Rockies...with model solutions now split into two 
distinct camps. Euro/UKMET/Gem eject a lead shortwave out of the 
system into Canada on Monday...and hang troughing back near The Four 
Corners through Tuesday before lifting this up across the Great 
Lakes on Wednesday. GFS and NAM solutions now keep the western 
trough intact and bring the whole system up across the northern 
Great Lakes on Tuesday. Will continue to follow the stronger 
consensus of the first group of solutions. This will push the 
initial cold front through the forecast area late Monday night and 
Tuesday...followed by another surface low pressure system and front 
on Wednesday. Inherited forecast which carried rain chances Monday 
night through Tuesday night continues to look in line with current 
thinking and little change was made. Thunderstorm mention still 
looks warranted as well as models continue to indicate good elevated 
instability. Only noticeable change to the forecast was to add 
chance probability of precipitation on Wednesday as the second half of the western trough 
lifts up across the region. Otherwise...after a warm start to the 
week...temperatures will fall down closer to their normal values in 
the low/middle 60s for the second half of the week. 


&& 


Marine... 


Southeast winds today will veer to the south on Sunday as high 
pressure across the eastern Great Lakes moves off to the east as a 
low pressure system develops across the plains. The southerly winds 
will mean waves will be fairly low across the nearshore 
waters...while the open waters could see locally higher waves up to 
6 feet with a greater fetch. 


The low will move into the western Great Lakes on Monday...and bring 
a cold front through the central Great Lakes as the low passes 
through southern Canada on Tuesday. Winds will be gusty as the front 
moves through on Tuesday...with 25 to 30 knot gusts causing rough 
boating conditions. 


&& 


Previous discussion...issued 101 am EDT Sat Oct 11 2008 


Aviation... 


The large high pressure system over the eastern lakes will maintain 
VFR conditions and light winds through the morning. Southeasterly 
winds on the order of 8 to 10 knots will develop by early afternoon 
as mixing depths increase. 


&& 


DTX watches/warnings/advisories... 
Michigan...none. 
Lake Huron...none. 
Lake St Clair...none. 
Michigan waters of Lake Erie...none. 


&& 


$$ 


Short term...kurimski 
long term....hlo 
marine.......kurimski 
aviation.....Kurimski 




You can obtain your latest National Weather Service forecasts online 
at www.Weather.Gov/Detroit (all lower case).