480 
fxus63 kdlh 181534 aaa 
afddlh 


Area forecast discussion...updated 
National Weather Service Duluth Minnesota 
1034 am CDT Friday Jul 18 2008 


Update...adjusted temperatures up a based on surface heating trends this 
morning. Forecast soundings do show good lower tropospheric mixing 
this afternoon. With sufficient low level residual moisture 
present...should see broken cumulus field develop as well this afternoon. 
Also expecting ridging aloft to prevent instability showers/thunderstorms 
from developing. High pressure will move off to the northeast 
tonight...and with easterly return flow setting up...have added 
fog for tonight. 


&& 


Previous discussion... /issued 346 am CDT Friday Jul 18 2008/ 


Discussion...latest surface analysis shows a weak summertime pressure 
gradient over the central part of the country...with a weak cold 
front draped across the upper Midwest from southern Minnesota NE across northwestern 
WI and over Lake Superior. This front has been the focus for 
shower and thunderstorm development over the last day or two. 
However dry conditions prevail across our forecast area 
currently...with areas fog affecting locations near Lake 
Superior and across northwestern southeast of the front. The front will continue 
its slow track to the south today...taking it all the way through 
our County Warning Area by midday today. Very weak high pressure with somewhat 
drier air will move in across the Northland today and 
tonight...resulting in dry conditions and near normal temperatures. The 
high pressure ridge axis will drift east of our forecast area by 
Saturday...causing winds to turn out of the 
east/southeast....resulting in onshore flow and cooler temperatures near 
Lake Superior for this weekend. 


The NAM and GFS solutions diverge at this point...with the NAM 
bringing a fair amount of moisture to the Northland this weekend 
as a shortwave propagates eastward across the upper Midwest. The GFS 
shows this shortwave as well...but it is less organized and the 
moisture is not as abundant. Other operational models including the 
European model (ecmwf) and Canadian trend closer to the NAM for this weekend. 
Therefore we will follow the NAM solution. 


The fog is expected to linger through the early morning 
hours...and dissipate by midday. The fog will be thickest near and 
over Lake Superior...so will issue a marine fog advisory for this 
morning. 


Aviation...patchy LIFR conds inland in ground fog will dissipate during the morning. 
VFR mostly clear will follow...and continue this evening. Patchy dense ground fog will return 
aftr 06z Sat. 


&& 


Point temps/pops... 
dlh 78 56 71 53 / 10 10 30 40 
inl 77 52 78 53 / 10 10 30 40 
brd 81 57 78 58 / 10 10 40 30 
hyr 81 53 78 57 / 10 10 30 40 
asx 78 53 73 56 / 10 10 20 40 


&& 


Dlh watches/warnings/advisories... 


Minnesota...none. 
WI...none. 
Ls...none. 


$$ 


Liles