Area Forecast Discussion
Issued by NWS Goodland, KS
FXUS63 KGLD 292334
Area Forecast Discussion
National Weather Service Goodland KS
534 PM MDT FRI JUL 29 2016
.SHORT TERM...(This evening through Saturday)
Issued at 222 PM MDT Fri Jul 29 2016
Another tedious/uncertain precipitation forecast. Persistent and
narrow band of light precipitation has been slowly decreasing
through the day. This area had persistent cloud cover and much
cooler temperatures and consequently will be much more stable.
Main shortwave looks to move across the southwest quadrant of the
area, south of where the light precipitation band is currently.
The convective allowing models confirm that by taking a cluster of
storms across that same area which was not adversely affected by
the persistent cloud cover and light rain.
So have slight chance to low chance in the far western and
southern areas. The question is what to do with the rainfall
forecast after midnight. Additional shortwave energy and mid level
warm air advection work its way across the eastern portion of the
area. Inserted slight chance there for after midnight which
continues/lingers in the far east Saturday morning. Toyed with
inserting fog into the grids later tonight and Saturday morning
but decided against it since the Nam was the only model really
indicating. The 18z run also reduced its area from the 12z run.
Another shortwave trough moves in from the the west on Saturday.
Inserted slight chance/low chance pops ahead of the shortwave on
.LONG TERM...(Saturday night through Friday)
Issued at 203 PM MDT Fri Jul 29 2016
Chances for precipitation during the extended period looks favorable
but there are different driving factors to create PoPs. As for
Saturday night, the CWA starts to become engulfed in a ridge that is
moving in from the west. The current NAM model run shows the region
to be dry due to the ridge cutting off the moisture inflow from the
southwestern states. Yet, the GFS has higher precipitation chances,
especially in the eastern half of the CWA. This is primarily due to
the moisture still moving into the region from the southwestern
states and a shortwave moving through the mid-levels. So storms can
not be ruled out at this time.
Sunday through Tuesday, the pattern will be fairly consistent with
the CWA being under a ridge. Embedded mid-level shortwaves are
showing to move over the region each day and moisture from the Gulf
of California will enhance storm potential each day.
Wednesday shows an upper level flow pattern change over the CWA. A
low pressure earlier in the week moves into the Pacific Northwest
and begins to push along the USA, Canadian border. So come
Wednesday, the ridge pushes east and troughing starts to impact the
region bringing with it a cold front. So moisture being pulled up
from Arizona and the cold front pushing through, precipitation
chance are much more probable on that afternoon into the overnight
Thursday into Friday will change patter wise. For Thursday, the
upper level pattern will push the trough east and create a zonal
pattern, for the most part, over the CWA. As the day progresses a
shortwave pushes through and enhances precipitation potential.
Friday will start to see ridging that pushes in from the west. PoPs
are still possible due to another embedded shortwave.
Temperatures will increase into the mid to upper 90s Sunday through
Wednesday and then drop into the 80s Thursday and Friday in the wake
of the cold front.
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 534 PM MDT Fri Jul 29 2016
For KGLD...Mainly VFR conditions thru the period. 02z-05z vcts
possible. 10z- 18z will have MVFR ceilings around bkn010-025...w/
5sm in fog thru 14z. Winds SSE around 10kts w/ gusts to 20kts
after 18z Saturday.
For KMCK...VFR thru the period with a mix of scattered low/mid
clouds. Winds SE around 10kts...w/ gusts to 20kts after 18z