463 
fxus63 kdlh 211141 aaa 
afddlh 


Area forecast discussion...updated 
National Weather Service Duluth Minnesota 
641 am CDT sun Mar 21 2010 


Aviation...12z taf issuance... 
an area of middle/hi level clouds will sweep across the region next 24 
hours as County Warning Area remains under influence of upper jet stream. A surface cold 
front just north of the border will drop south towards kinl by 
15z. Lowering cloud bases will develop near kinl...but then dissipate by 
early afternoon. Should be a close call but will keep bases in VFR 
category. Elsewhere VFR will prevail as lack of low level moisture 
will limit any significant cloud development. Periodic batches of 
middle/hi level clouds are expected. 




&& 


Previous discussion... /issued 351 am CDT sun Mar 21 2010/ 


The forecast area remains positioned between a well defined frontal boundary 
located just north of the international border...and a strong low 
pressure system affecting the southern half of the Continental U.S.. only 
adjustments to short term were to decrease dew points/relative humidity values today 
and Monday as dry air mass centers over the Northland. Went with 
similar conditions as observed yesterday where afternoon dew 
points were in the teens to single digits and relative humidity values were in 
the 20-30 percent range. Sunny skies will prevail today...with 
some middle level clouds associated with the cold front lingering in 
the Borderland this morning. Winds will be west to 
southwest...veering south overnight and into Monday as low 
pressure approaches from the west. The advancing trough will 
result in persistent warm air advection/thickness rises as the region remains in 
the warm sector through Monday. 


Extended...Monday night through Thursday... 
westerlies maintain split flow characteristic across Continental U.S. This 
period with County Warning Area underneath influence of northern branch. A weak middle level 
system with associated surface boundary will push across region Tuesday 
with light quantitative precipitation forecast. Ptype issues still messy.. however no significant 
problems anticipated at this time. Middle level flow intensifies 
Wednesday as upper low deepens over Hudson Bay. This makes for a 
quick moving surface high Wednesday across County Warning Area before next system 
approaches Wednesday night. Will keep inherited forecast of some light snow 
across mainly northern half of County Warning Area late Wednesday night...however suspect 
that we may end up seeing some light quantitative precipitation forecast farther south Thursday 
morning. Latest guidance is trending stronger with this system in 
terms of its thermal/kinematic fields. May actually have a brief 
burst of MDT snow along fairly deep frontogenesis zone near surface 
boundary before it pushes rapidly southward. 850 mb temperatures anomalies drop 
significantly by end of week so should see a notable drop in maximum 
temperatures thur/Fri. 


Aviation...06z taf issuance... 
approaching front this period with some increase in middle level 
clouds.Otherwise VFR expected. 




&& 


Point temps/pops... 
dlh 50 30 50 33 / 0 0 10 10 
inl 44 29 48 31 / 10 10 10 20 
brd 51 29 55 36 / 0 0 10 10 
hyr 53 22 57 36 / 0 0 10 10 
asx 51 26 53 34 / 0 0 10 10 


&& 


Dlh watches/warnings/advisories... 
Minnesota...none. 
WI...none. 
Ls...Small Craft Advisory until noon CDT today for lsz121-142>148. 


Small Craft Advisory until 4 PM CDT this afternoon for lsz140- 
141. 


&& 


$$ 


Graning/Cannon/Cannon