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fxus63 ksgf 182007 
afdsgf 


Area forecast discussion 
National Weather Service Springfield MO 
307 PM CDT Thursday Mar 18 2010 


Discussion... 


Sunshine returned to the area Thursday lifting temperatures into 
the upper 50s to lower 60s. Surface high pressure will slide off 
to the east tonight while the next upper trough to impact the region 
develops over The Rockies. 


A surface front will take shape from the plains into the Midwest 
Friday ahead of this upper trough. Increasing southerly winds and 
ample sunshine will warm temperatures well into the 60s. This along 
with a lingering dry airmass will result in heightened fire 
danger. 


The upper trough will dig into the plains Friday and Saturday 
while a cold front progresses eastward into the Ozarks. The front 
will be near the Missouri Kansas border by day break Saturday and 
east of the Ozarks by late Saturday. Rain and embedded thunder 
will overspread the region from west to east late Friday night 
into Saturday. Instability will be limited and severe weather is 
not expected. Widespread moderate to locally heavy rainfall will 
be possible given the persistent nature of the event. This could 
result in localized flooding and significant river rises. 


An upper low will close off across the Southern Plains Saturday 
then migrate eastward. This will prolong precipitation while 
colder air filters into the area. The evolution of this system 
along with temperature profiles remain highly uncertain. At this 
time it appears a mix of rain and snow will develop Saturday from 
southeast Kansas into central Missouri and translate eastward 
across much of the Ozarks Saturday night. Model soundings 
suggest all snow will develop from southeast Kansas into 
southwest and central Missouri by later Saturday afternoon and 
evening. Surface temperatures generally near or above freezing 
along with relatively warm ground temperatures will likely inhibit 
significant snow accumulations through the day Saturday. A higher 
potential for accumulating snow will develop Saturday night and 
perhaps into Sunday as surface temperatures cool. At this 
time...it appears accumulating snow is most likely across 
southeast Kansas into central and far southwest Missouri. 


A mix of rain and snow will persist into Sunday with temperatures 
in the 30s and gusty north winds. Improving weather conditions 
will return early next week as the upper low exits to the east. 


Foster 


&& 


Aviation... 


A stratus deck with high end MVFR ceilings continues to dissipate 
this afternoon from surface high pressure moving through 
southwest Missouri and the March sun angle. Surface winds will 
become southerly as this high builds east of the aerodromes. 
Surface winds will increase Friday morning in response to a 
tightening pressure gradient with low pressure deepening in the 
plains. Following the dispersal of the lingering stratus 
deck...VFR conditions are anticipated through the taf period. 


Angle 




&& 




Fire weather... 


A height end fire weather concern continues for Friday. The 
pressure gradient will tighten up with the approaching 
system/cold front on Friday. Prognosticated soundings indicate dry air in 
and just above the mixed layer which will likely mix down in the 
afternoon. For Friday afternoon dew points...an approximation of 
the NAM mixed layer dew points in the 0-1km layer were used. This 
would be a few degrees below MOS guidance. Relative humidity values will be near 
or just above red flag criteria (25 percent) Friday afternoon with 
winds just below criteria over the western portion of the forecast 
area. With recent moist weather...not expecting much problem with 
larger 10-100 hour fuels...but grassland/1-10 hour fuels will still be 
a concern. Will continue to mention in the hazardous weather 
outlook. 


Dsa/Foster 


&& 


Sgf watches/warnings/advisories... 
MO...none. 
Kansas...none. 
&& 


$$