149 
fxus63 kiwx 282339 
afdiwx 


Area forecast discussion 
National Weather Service northern Indiana 
738 PM EDT Thursday Aug 28 2008 


Aviation... 


Approaching middle level trough and associated cold front will move 
through ksbn overnight and through kfwa Friday morning. Satellite 
and radar showing convective complex across northern MO that will 
follow instability southeast and miss taf sites overnight. Latest 
radar showing developing line of thunderstorms and rain along front across eastern WI. 
This current activity likely to miss taf sites to the north but some 
development southward being observed. With loss of sun and heating 
any additional development will be tough. However...modest low level 
Theta-E moisture advection ahead of front coupled with a weak low 
level jet may be enough to support widely scattered rain showers or thunderstorms and rain on or 
just ahead of front. Coverage not expected to be great so have not 
introduced any mention into tafs at this time. Will monitor 
development for updates. Observations near front indicate 2-3kft 
ceilings and some MVFR br so have included this overnight with light 
wind field. Drying and clearing behind front on Friday so should see 
ceilings rise before clearing works in during the day. 


&& 




Short term...(tonight through Friday night) 
eastern extent of precipitation shield associated/west Illinois mesoscale convective system dwindling rapidly in 
subsident sink along western periphery of Fay remnant this afternoon. Mbe 
will likely continue southeastward given favorable downstream destabilization and 
something 12z GFS captures fairly well. However...as eluded to 
yesterday...secondary SW trough over Minnesota will lift northeastward into Ontario 
overnight which basically orphans surface frontal zone. This again 
confirmed by rapid frontal scale circ breakdown seen in most short 
range model solutions and will again minimize overall pop mention 
overnight/Friday am. More likely near term scenario is for renewed 
conv development over eastern Iowa/western Illinois this afternoon along western edge of shallow 
outflw bubble left over from morning storms. Some of this may hold 
eastward into northwest in/SW Michigan this evening but will encounter an 
increasingly hostile environment west/eastward extent. 


Otherwise temperatures look good. 


&& 


Long term...(saturday through thursday) 
warm and dry for the long term with good model 
agreement on strong ridging building over the Great Lakes into the 
middle of next week. 850 mb temperatures rise steadily peaking around 20-21c 
by Wednesday...with highs upper 80s approaching 90. With dry 
ground its possible we could get to low 90s on Tuesday/Wednesday but will 
remain on the conservative side for now as this is at the tail end 
of the period. 


Only hope for precipitation in extended is at the very end as GFS/ec bring 
middle level through through upper plains. Weak cold front moves near 
the region by Wednesday as whats left of Gustav moves up the lower 
Mississippi Valley. Given weak front heading into strong ridge and 
the presence of a tropical system working northward which tends to 
slow things down upstream...slower is the way to go. Thus...favored 
ec solution which is slower of the two and probably still not slow 
enough. Unfortunately for our very dry County Warning Area...the result is another 
dry extended forecast through the period but with the hope of precipitation 
lying just beyond. 


&& 


Iwx watches/warnings/advisories... 
in...none. 
Michigan...none. 
Ohio...none. 
Lm...none. 
&& 


$$ 


Short term...holsten 
long term...Ludington 
aviation...Lashley