Area Forecast Discussion
Issued by NWS North Platte, NE

Home | Current Version | Previous Version | Text Only | 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
FXUS63 KLBF 302046

Area Forecast Discussion
National Weather Service North Platte NE
346 PM CDT Thu Mar 30 2017

.SHORT TERM...(This evening through Friday)
Issued at 335 PM CDT Thu Mar 30 2017

The main sensible weather concerns in the short term period were
possible fog development after midnight and precipitation chances.
Latest water vapor imagery shows a sharp trough digging over the
West Coast and southwest flow over the Central Great Basin-Central
Rockies with a low amplitude ridge over the Central Plains.
Latest VIS and IR satellite imagery shows stratus in place over
much of north central and central NEB with high clouds over
western NEB.

Guidance is in good agreement with the large scale pattern in the
short term period. The mid-level trough will continue to amplify
and develop into a closed low this evening over the southwest US
and then the 500 hPa low will move slowly into the Four Corners
region tomorrow. Late tonight/early tomorrow morning the first
disturbance from the closed low is expected to lift northward
through western NEB. While not very deep, the positive PV anomaly
is expected to contribute to increased chances for precipitation
mainly to western NEB with the aid of modest isentropic ascent and
upward moisture transport. The combination of clouds and easterly
flow, the latter keeping cooler air entrenched aloft, will lend
to below normal highs tomorrow -- coolest in western NEB.

.LONG TERM...(Friday night through Thursday)
Issued at 335 PM CDT Thu Mar 30 2017

A unsettled weather pattern will affect western and north central
NEB this weekend and through much of next week. While the
likelihood for hazardous weather appears low, chances for rain
exist Friday Night through Saturday and Monday through Wednesday.
Outside of a rebound to slightly above normal temperatures Sunday
and Monday, highs are anticipated to read on the cooler side
compared to seasonal normal values.

The aforementioned 500 hPa closed low will be over the Four
Corners region at the start of the period with a shortwave ridge
extending from the Lower Mississippi Valley into the eastern
Central Plains. The mid-level low will weaken Friday Night through
Saturday as it drifts into the Southern High Plains. The highest
chances for precipitation with this system occurs Saturday
attributable to increasing large scale ascent and lower
tropospheric forcing. Precipitation chances then diminish after
midnight Sunday into Sunday morning from west to east. The
weakening 500 hPa closed low over the Southern High Plains will
weaken into an open wave Sunday as it moves into the eastern
Central Plains and eastern Southern Plains late Sunday.

Another upper level trough is then expected to amplify as it
tracks from the Pacific Northwest into the Central High Plains
over the period Sunday Night to Monday. While differences in phase
and amplitude exists with the handling of this system, confidence
is increasing that this system will spread precipitation across
much of the local forecast area late Monday to Wednesday.


.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
Issued at 1245 PM CDT Thu Mar 30 2017

Latest satellite imagery shows stratus still in place across the
eastern two-thirds of NEB with the western edge of the stratus
along a line roughly from Hayes Center to Sutherland to Eli.
High clouds are present elsewhere across western NEB and upstream
in the NEB panhandle. Ceilings are MVFR-IFR. Visibilities are
unrestricted with patchy fog having dissipated/lifted mid-late
morning. Aviation concerns the next 24 hours include flight
categories and precipitation chances.

Ceilings are expected to improve gradually this afternoon across
the aforementioned edge of stratus and eastward towards Highway
83. Elsewhere, current thinking is ceilings will likely not
improve across much of north central NEB with ceilings staying
sub-VFR. Ceilings will then deteriorate/stratus will work back
westward gradually this evening encompassing much of western NE
near midnight. Current thinking is after midnight there will be
increased chances for showers over mainly the eastern NEB
Panhandle. Generally MVFR to IFR conditions are expected to
prevail tomorrow morning.




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