471 
fxus63 kddc 210924 
afdddc 


Area forecast discussion 
National Weather Service Dodge City Kansas 
324 am CST Sat Nov 21 2009 


Discussion... 


Days 1-2... 


Lee troughing is beginning to strengthen over eastern Colorado as 
evidenced by pressure falls on the order of 1mb/hr. Winds over 
western Kansas are responding and are now largely from the S-SW. The 
exception is over central Kansas where there is still a bit of 
easterly component to the flow. As a result, moisture continues to 
advect into central Kansas and some low cloud is evident on 11-3.9 
satellite. This cloud deck is breaking up as it advances into Kansas 
and is not making much headway to the west so it shouldn't be much 
of a problem today. But there will be a bit of low cloud to start 
the day over the eastern third or so of the ddc forecast area. 


As an upper trough moves into the Great Basin today, surface pressure 
falls will continue over eastern Colorado. Middle levels winds will 
strengthen and begin to mix down as we warm up through the morning. 
Model winds for today are forecast in the 15-20 knots range over SW Kansas 
by this afternoon and this almost certainly underdone. Am expecting 
a breezy day today with a fair amount of sun before high clouds 
begin to move in during the afternoon. 


By tonight, the upper trough will move into Colorado. A 40-50kt low level jet will 
set up and this should keep surface winds up and provide for a milder 
night tonight, temp-wise. The upper trough will move through western Kansas 
Sunday along with a brief wind shift at the surface. This initial trough 
is pretty weak and with a much stronger trough coming into the west on 
its heals, surface winds will be sort of tricky. Models show a wind 
shift Sunday but then bring them right back around to the south by 
Sunday night as the stronger trough moves quickly into the northern/central 
rockies and Lee trofing resumes. Am not expecting any precipitation through 
the short term as dynamics and moisture are limited and the trough is 
coming from a direction generally unfavorable to precipitation. -Wright 


Days 3-7... 


The 00z runs of the GFS/European model (ecmwf) continue to be fairly consistent with 
their respective earlier runs with the evolution of the upper trough 
that digs into the central Continental U.S. Early next week. The GFS continues 
to be the farthest north...moving the upper low out across northern 
Nebraska while the European model (ecmwf) continues to close off the upper low over 
northern Kansas. The 00z Canadian has now has the upper low coming 
out farther north than previous runs. 


The European model (ecmwf) is still the most optimistic with precipitation over 
western Kansas which makes sense given its farther south track. It 
still has the best chances across the northern County Warning Area as the dry slot 
will be impacting areas farther south. Model 850 mb temperatures are 
not overly cool with temperatures late Monday into early Tuesday so 
a rain/snow mix still looks reasonable. Will keep the small probability of precipitation for 
Monday/Monday night in place for now. 


Winds will more than likely be the main issue. The European model (ecmwf) shows 
windspeeds at 850 mb increasing to 40+ knots Monday into Tuesday so 
their may be a period with winds exceeding advisory criteria. 


Later periods show the upper low continuing to move off to the east. 
Northwest flow aloft over the region will result in dry weather 
across southwest Kansas through the latter part of the week. 


&& 


Aviation... 


MVFR ceilings will prevail from Hays to east of Dodge City through the 
early morning hours but should dissipate by late morning. An upper 
level shortwave moving into the central rockies today will help 
strengthen a Lee side trough over the western High Plains. This will 
bring gusty south winds at 20 to 30 knots across southwest and 
central Kansas today. VFR conditions should prevail through the rest 
of the day. MVFR/IFR ceilings are possible again tonight mainly around 
Dodge City and Hays as low level moisture continues to spread into 
the area. 


&& 


Preliminary point temps/pops... 
ddc 60 38 53 35 / 0 0 0 10 
gck 60 36 55 33 / 0 0 0 10 
eha 61 36 55 34 / 0 0 0 10 
lbl 62 36 56 34 / 0 0 0 10 
hys 58 37 53 35 / 0 0 0 10 
p28 60 43 58 40 / 0 0 0 10 


&& 


Ddc watches/warnings/advisories... 
none. 
&& 


$$ 


Fn34/02/02