Forecast Discussion
NWS Omaha/Valley, NE

000
FXUS63 KOAX 232356
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
656 PM CDT Sun Jul 23 2017

.SHORT TERM...(Tonight through Monday Night)
Issued at 321 PM CDT Sun Jul 23 2017

As advertised, a somewhat cooler and drier airmass continues to
build south across the region today with temperatures ranging from
the middle 80s in northeast Nebraska to the lower 90s in far
southern reaches of the forecast area. Dewpoints have also dropped
considerably, with comfortable 55-63 degree dewpoints expected to
be common across the entire area by mid evening. Surface high
pressure will build southeast overnight with the surface ridge
axis extending down the Missouri valley by sunrise on Monday. This
should promote light or calm winds and effective radiational
cooling in the presence of remnant near-surface moisture. These
ingredients suggest at least the potential for patchy fog
especially in low areas along the Missouri Valley and eastward
into western Iowa. At this time, confidence in fog development is
low but if/where it does develop, some patchy dense fog is
possible.

On Monday, surface winds turn back out of the southeast with some
warm advection gradually nosing into the area. All-in-all it will
be a pleasant day especially when compared to the past week, with
near-normal temperatures expected. There is a vorticity maximum
currently very evident in WV imagery over SW Montana which will
slowly but surely track across southern South Dakota. This may
provide adequate lift to initiate convection late Monday into
Monday night mainly near the NE/SD border. Low levels will be very
dry but model soundings (and WV imagery) suggest mid-level
moisture associated with the system may support uncapped
convective parcels over far northern NE and perhaps into west
central IA. Severe potential is low as the elevated instability
and effective shear are not particularly impressive.

Warmer weather is expected Tuesday into Wednesday as south winds
increase and a strong short wave trough tracks across southern
Canada. This trough will push a cold front toward northern parts
of the forecast area by early Wednesday morning while reinforcing
short wave energy gradually pushes the front through the whole CWA
by Thursday. Should see quite a bit of convergence along this slow
moving frontal boundary while the interaction with the modified
monsoonal moisture plume and weak periods of mid/upper level
energy to produce a few rounds of thunderstorms. Have thus gone
with relatively high precip chances for the general Wednesday time
frame with the exception that the activity will be scattered in
nature and a few locations may still very well go untouched by
precipitation. In the end though, the slow movement of the system
and availability of multiple forcing mechanisms suggest that
higher end Pops are reasonable.

Temperatures behind this system may actually fall below normal for
multiple days as a northwest to nearly meridional flow pattern is
set to dominate the local forecast area.

.LONG TERM...(Tuesday through Sunday)
Issued at 321 PM CDT Sun Jul 23 2017

Warmer weather is expected Tuesday into Wednesday as south winds
increase and a strong short wave trough tracks across southern
Canada. This trough will push a cold front toward northern parts
of the forecast area by early Wednesday morning while reinforcing
short wave energy gradually pushes the front through the whole CWA
by Thursday. Should see quite a bit of convergence along this slow
moving frontal boundary while the interaction with the modified
monsoonal moisture plume and weak periods of mid/upper level
energy to produce a few rounds of thunderstorms. Have thus gone
with relatively high precip chances for the general Wednesday time
frame with the exception that the activity will be scattered in
nature and a few locations may still very well go untouched by
precipitation. In the end though, the slow movement of the system
and availability of multiple forcing mechanisms suggest that
higher end Pops are reasonable.

Temperatures behind this system may actually fall below normal for
multiple days as a northwest to nearly meridional flow pattern is
set to dominate the local forecast area.

&&

.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 654 PM CDT Sun Jul 23 2017

VFR conditions through the period. There may be some patchy MVFR fog
in the area 10-13z at KOMA.

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...None.
IA...None.
&&

$$

SHORT TERM...Barjenbruch
LONG TERM...Barjenbruch
AVIATION...DeWald

NWS OAX Office Area Forecast Discussion

Forecast Discussion
NWS Hastings, NE

761
FXUS63 KGID 232339
AFDGID

Area Forecast Discussion
National Weather Service Hastings NE
639 PM CDT Sun Jul 23 2017

.SHORT TERM...(This evening through Monday)
Issued at 250 PM CDT Sun Jul 23 2017

Dry and relatively mild weather will prevail through the rest of
today and Monday. Light northerly winds will go light and variable
tonight, before shifting to the south for Monday morning as high
pressure moves off to the east. Winds tomorrow will likely be more
breezy than today, possibly gusting to 15-25 MPH during the
afternoon.

.LONG TERM...(Monday night through Sunday)
Issued at 250 PM CDT Sun Jul 23 2017

The long-term period begins off dry as well, but continued southerly
flow means that Tuesday will be notably warmer once again. Highs
are expected to range from the low to the upper 90s. Dewpoints in
the mid to upper 60s may push heat index values to around 100
degrees across the area. While not as hot as last week, it will
probably end up being the hottest day of the week.

Chances for rain and thunderstorms return to the forecast area late
Tuesday night as a cold front drops southward towards the forecast
area. Models vary a little bit on the timing of this front, but
the overall consensus is that it will be draped across the area
Wednesday afternoon and evening, allowing for scattered
thunderstorms to develop. The GFS isn`t particularly concerning
from a severe weather perspective...around 1000-2000J of MUCAPE
and 25-25 kts of deep-layer shear...but I would expect to see a
"marginal" risk be introduced tomorrow, at least for parts of the
area. Of course, this will likely be affected by mesoscale
features from previous convection (outflow boundaries, lingering
cloud cover, etc.)

Chances for thunderstorms gradually shift southward through the day
Thursday. Most of the area will dry out by late afternoon, but a
few storms could linger across Kansas through the overnight into
Friday morning.

High temperatures Wednesday and Thursday are expected to be much
cooler and will range from the low 80s to the mid 90s. These
temperatures will be greatly influenced on timing of precipitation
and sky cover.

Late next week into the weekend, we will move into more
northwesterly flow aloft, leading to primarily dry conditions. Even
so, I`ve kept isolated chances for storms as a few quick-moving
disturbances are indicated by both the GFS and ECMWF...albeit at
varying times. Temperatures are expected to stay in the upper 80s to
low 90s Friday through next Sunday as well.

&&

.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Monday)
Issued at 628 PM CDT Sun Jul 23 2017

VFR conditions will continue to prevail across the forecast area.
The wind will gradually shift from easterly tonight to a more
southeast or even southerly wind on Monday.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...None.
KS...None.
&&

$$

SHORT TERM...Mangels
LONG TERM...Mangels
AVIATION...Wesely

NWS GID Office Area Forecast Discussion