355 
fxus63 kgid 182010 
afdgid 


Area forecast discussion 
National Weather Service Hastings NE 
310 PM CDT Friday Jul 18 2008 


Short term...through Saturday night. Again time today has been 
precious. It appears we will miss any major weather tonight...as 
the County warning forecast area in the wake of large mesoscale convective vortex rotating east of the area...and 
we have dealt with a ton of low clouds just starting to break up 
at the time. Water vapor suggests area to our south will be more 
likely for thunderstorms tonight...as wave comes of the southern 
rockies and interacts with boundary in southern Kansas. Some of 
those showers/storms could clip the southeast County warning forecast area...where slightly 
higher precipitation chances were kept. To the north...the question 
is will anything which develops near the Black Hills be able to 
reach the County warning forecast area. Most 12z models suggest no on that question. No the 
18z NAM points to the same solution. Have lower precipitation 
chances. 


On Saturday...we may battle a bit of fog/low clouds in the morning 
and the next shift will want to gage that. Looks quite a bit 
warmer with southerly flow developing. A weak front will slink into 
the northern County warning forecast area by evening...and may provide enough lift to 
trigger some isolated thunderstorms in the north/northeast County warning forecast area. 
This front could have a bit more push with outflow from South 
Dakota storms. Kept the small risk in that area for late Saturday 
afternoon and night. Thinking the western/southern County warning forecast area should 
capped. That cap may actually be an issue for the entire County warning forecast area...as 
700 mb temperatures on the 18z NAM are +13-14. Doubtful we would bust that. 


Long term...Sunday through Friday. The extended periods are not 
completely clear cut by models and although the extended is dry for 
the most part...this will ultimately depend on how the ridge axis 
sets up or whether it retrogrades or gets shunted south as waves top 
it. On Sunday the ridge axis builds north and east onto the plains 
and the heat moves in. Temperatures will rise well into the 90s and 
should even top 100f in our south and west. A frontal boundary near 
the South Dakota/Nebraska border will be the focus for potential 
convection. Convective available potential energy increase across our northern counties and the 
main question is whether or not convection to the north will reach 
our County Warning Area or not late Sunday. Latest day3 outlook has a slight risk 
for severe weather and our current forecast has some low probability of precipitation in. 
Believe the best thing to do is to leave this alone and see whether 
or not models trend farther north with this or not. Capping should 
strengthen with warming middle level temperatures with building ridge 
into next week. If the ridge retrogrades around middle week...then 
some storms may sneak in...but at this time models are not consistent with 
this. Ensembles indicate really do not indicate much in the way of 
precipitation next week and the European model (ecmwf) is similar...the latest GFS as well as 
HPC suggest some chances but confidence is not high enough to 
include. Temperatures will be very warm as the heat turns with the 
upper ridge in place with readings reaching into the 90s to near 
100f through at least about middle week. Apparent temperatures may 
near heat advisory criteria and may need to monitor this. 


&& 


Previous discussion... /issued 1241 PM CDT Friday Jul 18 2008/ 


Aviation...18z taf. MVFR ceilings are expected through the afternoon 
at the kgri Airport. There will be some lifting of ceilings this 
evening to VFR levels...but then back down to MVFR ceilings and visibilities 
in haze/br overnight. Winds will be light and variable initially... 
and gradually turn to the south. Risk for additional showers/storms 
looks minimal. 


&& 


Gid watches/warnings/advisories... 
NE...none. 
Kansas...none. 
&& 


$$