Area Forecast Discussion
Issued by NWS North Platte, NE

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
FXUS63 KLBF 231126

Area Forecast Discussion
National Weather Service North Platte NE
626 AM CDT Sun Jul 23 2017

.SHORT TERM...(Today and tonight)
Issued at 342 AM CDT Sun Jul 23 2017

Weather highlights the next 24 hours include: slightly warmer
temperatures than yesterday, mostly clear skies, and light winds.
Highs largely in the lower to mid 90s today, about 4-8 degrees
above seasonal normal values. Overall, quiet weather is
anticipated through tonight with models largely in good agreement.
Latest IR and NtMicro satellite imagery at the top of the hour
shows clear skies overhead. Latest water vapor imagery shows
modest amplified mid- level flow over the CONUS with a shortwave
trough moving into the Upper Great Lakes from the Upper Midwest
and a broad ridge over the Southwest US extending into the
southern Canadian Prairies with an shortwave trough apparent over
southern ID. Latest surface plot shows high pressure at the
surface that extends into western NEB from western ND with a
central pressure near 1017 mb.

Very little change with the large scale pattern with small height
rises today with the upper level ridge just shifting slightly
eastward. Warmer 850 temperatures compared to yesterday as seen with
model soundings. 850 hPa temperatures range from about 22-29 C this
afternoon, warmest in the west. These temperatures aloft combined
with a well-mixed boundary and excellent insolation should be
conducive for highs in the lower to mid 90s. Columns largely dry so
anticipated sunny/mostly sunny skies. Thereafter expect some high
clouds moving into western and northern NEB this evening. Lows
tonight are expected to read in the low to mid 60s.

.LONG TERM...(Monday through Saturday)
Issued at 342 AM CDT Sun Jul 23 2017

An H5 ridge builds over the Plains early in the week, then retreats
west as a trough digs over the Great Plains midweek, placing
Nebraska in broad northwest flow. The synoptic pattern at the
surface is dominated by a slow moving low pressure and cold front
across the northern/central Plains, which crosses western Nebraska
on Wednesday.

Monday and Tuesday... The sfc low develops near the WY Black Hills
on Monday, dragging the trough along the high plains of WY and CO.
The trough, along with the higher terrain, will provide the forcing
and lift for convection. Forecast soundings show relatively slow
storm motion, generally 10-12 kts, and dry air in the low levels.
These factors will keep coverage isolated and not move the storms
into the eastern panhandle until late evening. The boundary bisects
northwest Nebraska Tuesday evening, bringing the focus for
convective initiation into the forecast area. Mid level moisture
increases Tue evening, and with the LLJ nose near the NE/SD border,
raised PoP to chc for most of the Sandhills. Low CAPE and deep layer
shear will limit the severe coverage and potential. Heavy rain
threat increases Tuesday as PWATs rise toward 1.5" and storm motion
remains around 15 kts. Temperatures trended up slightly both days as
the thermal ridge takes hold. Breezy south winds, a deep mixed
layer, and H85 temps around 30C will lead to highs in the mid to
upper 90s. Some spots will likely hit 100F again, mainly far SW Neb
and near VTN.

Wednesday... The ECM and GFS are in better agreement concerning the
fropa. The 00z suite trended faster, bringing the front through the
Sandhills by Wed afternoon. As a result, max temps were dropped into
the 80s. A secondary sfc low develops in western KS, helping to draw
moisture into the area, especially SW and central Neb. Dew points
will likely reach the upper 60s. Despite the early onset of clouds
and precip, GFS soundings indicate a good deal of elevated CAPE Wed
aftn. Can`t rule out a severe storm as 0-6 km bulk shear approaches
35 kts.

Thursday through Saturday... A sfc high drops into the Upper Miss
Valley, setting up return flow for western Neb. This will also lead
to an extended upslope regime. With another trough rounding the
mountains Saturday, downstream convection may be an issue for the
panhandle. Temperatures will remain near season averages in the wake
of the front, translating to upper 80s to lower 90s.


.AVIATION...(For the 12Z TAFS through 12Z Monday morning)
Issued at 623 AM CDT Sun Jul 23 2017

Satellite imagery reveals largely clear skies overhead. Surface
plot shows a few sites seeing a reduction in visibility due to fog
in south central NEB. Current thinking is portions of the local
forecast area in the east and south may see some light patchy fog
this morning but not significant impacts are expected. Light
winds will prevail over the next 24 hours (less than 10 kts) along
with VFR ceilings and dry conditions.




LONG TERM...Snively
AVIATION...ET is the U.S. government's official web portal to all federal, state and local government web resources and services.