Forecast Discussions mentioning any of
"ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 06/07/20
Area Forecast Discussion
National Weather Service Denver/Boulder CO
828 PM MDT Sat Jun 6 2020
.UPDATE...
Issued at 827 PM MDT Sat Jun 6 2020
The last of the convection is over the far northeast corner of the
CWa right now; Phillips and Sedgwick Counties. It is completely
clear over the western 3/5ths of the CWA right now, and should be
over all the CWA by around 05Z. Models keep fairly strong
southwesterly flow aloft overnight. The normal drainage winds
patterns overnight should have some southwesterlies mixed in. Will
make sure the sky and wind GFE grids are in line. Overnight lows
should get significantly closed to the normal seasonal lows than
this morning readings were. Concerning the Red Flag Warning. Will
leave is going as decent winds will kick up early Sunday morning.
&&
.SHORT TERM...(This evening through Sunday)
Issued at 248 PM MDT Sat Jun 6 2020
Current surface analysis shows surface low in southeast Montana,
with a lee trough intensifying along the Front Range. Satellite
shows an impressive comma head in northeast Utah moving
northeast, with an intense line of convection stretching south
from that through central Colorado.
High winds have developed from the eastern side of Denver metro
across the Palmer Divide, and stronger wind core is expected to
shift slightly eastward through late afternoon and early evening.
We`ll keep the existing warnings in tact. Convection is expected
to spread east across the plains in these late afternoon and
evening hours, as airmass seems to be approaching convective
temperatures per latest AMDAR sounding data, satellite, and radar.
Given the 50-60 knots of wind as seen on latest vad wind profiler
between 8000 and 10000 feet MSL, only an extra 15 knots added to
that from the DCAPE near 1000 J/kg would support damaging surface
wind gusts of 70-85+ mph. Some of those wind speeds have already
been observed with storms in western Colorado, and don`t see much
difference for our forecast area given the location and strength
of low/mid level wind speed core. MLCAPE is limited to about
500-800 J/kg, so main threat appears to be wind across our
forecast area.
The back edge of storms should pass to the east of the I-25
Corridor by 6 PM, and then exit the eastern plains by 10 PM.
Clearing skies and lighter winds thereafter.
On Sunday, mostly sunny but dry conditions will prevail, and winds
will again increase in the afternoon. Temperatures will push 90F
or more across most of the plains. There is just enough moisture
over the northwest portion of the state to keep a chance of
showers and storms over the north central mountains for the
afternoon.
.LONG TERM...(Sunday night through Saturday)
Issued at 248 PM MDT Sat Jun 6 2020
Will be keeping an eye on Monday and Monday night`s weather as
an upper trough from the Pacific Northwest is forecast to move
across the northern half of the state. Latest model runs have been
slowing this feature down, in deference to Tropical Storm
Cristobal which is forecast to be tracking northward up the Lower
Mississippi Valley. The motion of the tropical system will be
blocking the prevailing westerly flow pattern across the country.
As the upper trough slows its motion, it will be undergoing some
amplification with cold air aloft dropping down from the northern
Rockies. This will drop snow levels down below 10,000 feet from
Monday afternoon through Tuesday morning. The period of heaviest
precipitation with this system will be Monday evening when
mountain ridges may pick up a few inches of snow accumulation.
Impact on roads should be minimal, this late in the season. On the
plains, the combination of dynamic forcing and daytime heating
should be enough to drive the formation of afternoon and evening
thunderstorms. At the current time there is a marginal risk that
some of the thunderstorms could reach severe limits. Cloud cover
through the day will help keep temperatures cool, as well as some
northerly flow out ahead of an approaching cold front. All in all,
Monday will be the third active day in a row for northern
Colorado.
The GFS and ECMWF show the core of the upper trough over northeast
Colorado Tuesday morning, moving out the state by evening.
Temperatures across the forecast area will be quite cool, only in
the upper 60s and lower 70s across the plains and 30s and 40s in
the mountains. Behind the passing trough it should be quite
subsident so no precipitation is expected after Tuesday morning.
The rest of the week will feature an upper ridge re-building over
the Southern Rockies with a gradual warming trend across north
central and northeast Colorado. By late in the week we should
again see the return of afternoon and evening thunderstorm
activity. By next Saturday, high temperatures will probably be
getting back close to 90.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 827 PM MDT Sat Jun 6 2020
Drainage winds should prevail at DIA by 04-05Z this evening.
Pretty strong south-southwesterly winds should kick in Sunday
morning by 15-16Z. There should be no more precipitation at DIA
until later On monday. No ceiling issues are expected tonight or
Sunday.
&&
.FIRE WEATHER...
Issued at 248 PM MDT Sat Jun 6 2020
Strong winds combined with warmer than average temperatures will
keep fire danger high across the eastern plains into early this
evening, despite the marginal humidity values. However, given
the magnitude of winds any fire could spread rapidly out of
control.
Continued critical fire weather conditons expected again on
Sunday afternoon. Good mixing will result in southwest wind
gusts up to 40-45 mph by afternoon. Humidity levels will be lower
than today so critical fire weather conditions will redevelop over
east central Colorado and the Palmer Divide where fuels are
driest. We`ll also issue a Red Flag Warning for the southern
foothills and Park County (Zones 214 and 216) where it will be
drier tomorrow.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning until 9 PM MDT Sunday for COZ241-245>251.
Red Flag Warning from noon to 9 PM MDT Sunday for COZ214-216.
&&
$$
UPDATE.........RJK
SHORT TERM.....Barjenbruch
LONG TERM......Dankers
AVIATION.......RJK
FIRE WEATHER...Barjenbruch
Area Forecast Discussion
National Weather Service Wichita KS
636 PM CDT Sat Jun 6 2020
.SHORT TERM...(This evening through Tuesday night)
Issued at 344 PM CDT Sat Jun 6 2020
This afternoon, a very amplified pattern exists across the CONUS,
with a pronounced upper level trough over the WRN US, and anomalous
ridging over the central US. At the SFC, low pressure is situated
over WRN SD. A warm front stretches southeast into NRN MO, with a
trough/dryline stretching south in the lee of the Rockies. Continued
southerly flow and less mixing has allowed low to mid 70s dewpoints
to be realized across ERN KS, with heat indices of 100-105
along/east of I-135 (peak values of around 105 have been observed
at Chanute and Independence). Further west, deeper mixing is
keeping dewpoints in the low to mid 60s, with heat indices holding
around 100.
The SFC trough/dryline will retreat tonight, then mix east again on
Sunday, reaching central KS in the afternoon (possibly a bit further
east than it reached today). We`ll probably still hold some
dewpoints in the low-70s across southeast KS tomorrow afternoon
where mixing will be less prominent, but afternoon highs may
actually drop 1-3 degrees as 850mb temps potentially cool ever-so-
slightly. The net result is heat indices running a bit lower than
today. For these reasons, we`ll hold off on re- issuing a Heat
Advisory for tomorrow afternoon. Still looking at heat indices
around 100, though.
As the SFC trough/dryline mixes east tomorrow, a tightening pressure
gradient combined with steep lapse rates, deeper mixing, and
increasing winds aloft will support wind gusts around 40 mph across
central KS, with a few gusts to 45 mph plausible. Some model
guidance continues to suggest the potential for gusts to flirt with
Wind Advisory criteria, but we`ll hold off given the lower coverage
and more marginal nature.
Across southeast KS, still cannot rule out a popup shower or
thunderstorm this afternoon or again Sunday afternoon, but warm mid-
level temps, drier air well north of Cristobal, and a lack of any
appreciable forcing should keep this threat at a minimum.
Martin
.LONG TERM...(Wednesday through Saturday)
Issued at 344 PM CDT Sat Jun 6 2020
As of 1 pm, TS Cristobal was located over the central Gulf of
Mexico, with a forecast landfall along the Louisiana coast tomorrow
evening. A NNW movement is forecast through the Lower MS Valley on
Monday, followed by a more N/NE movement through the Ozarks and into
the Great Lakes TUE-WED. Cristobal will merge with the WRN US trough
(advancing east across the central US), eventually carving out a
deeper trough/upper low over the Great Lakes/central Canada by mid-
week.
The latest trend with Cristobal is a slightly further east track,
which leads to an even lower probability of seeing much in the way
of precipitation for far southeast KS. Cooling temps aloft and a
slight increase in convergence to the NW of Cristobal may lead to a
few showers along/east of the Flint Hills Monday into Monday night,
possibly catching some far western reaches of the system as it
passes through the Ozarks, but impacts look very low.
As the SFC and upper level system deepens over the Plains, a strong
cold front/dryline will advance quickly east across Kansas
Tuesday in a much more spring-like fashion. If enough low-level
moistening can occur ahead of the front/dryline, there may be
enough forcing for at least a short window of opportunity for a
few storms to develop during peak heating, when inhibition will be
the lowest. This potential may be limited due to subsidence on
the backside of Cristobal`s remnants, but something to watch in
future model runs/forecasts. Stronger deep layer shear will be in
place across the area on Tuesday with the deepening mid-latitude
system, which could support a conditional, isolated severe threat
should enough moisture and forcing be realized.
In the wake of the front/dryline, strengthening W/NW winds aloft and
deeper mixing could support a period of stronger wind gusts
(possibly near Advisory criteria once again). Additionally, a surge
of cooler temps aloft (5-10C) in the wake of the front may allow
temps to fall into the upper 40s to mid 50s by Wednesday morning,
especially if winds can relax enough. Dry, stable air may remain in
place for the remainder of the work week, keeping temperatures
closer to normal and the threat of storms low.
Martin
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 633 PM CDT Sat Jun 6 2020
VFR conditions are expected to dominate throughout the TAF
period. Ridging is expected to continue and hot summer
temperatures can be expected. This could create some density
altitude issues for aircraft sensitive to high summer
temperatures. The only issue for the overnight period will be the
development of some LLWS at KRSL terminal. These wind shear
conditions should abate as the wind picks up after sunrise
tomorrow. Otherwise, VFR conditions are expected to dominate.
Metzger
&&
.FIRE WEATHER...
Issued at 344 PM CDT Sat Jun 6 2020
South winds gusting to 35-45 mph and relative humidity values of
25-30 percent will be in place across central Kansas Sunday
afternoon. Gusty west winds and lower humidity may return Tuesday
afternoon as well.
&&
.PRELIMINARY POINT TEMPS/POPS...
Wichita-KICT 73 94 72 93 / 0 0 0 0
Hutchinson 73 95 70 93 / 0 0 0 0
Newton 72 93 71 91 / 0 0 0 0
ElDorado 72 91 70 90 / 0 0 0 10
Winfield-KWLD 72 93 71 92 / 0 0 0 0
Russell 73 96 71 95 / 0 0 0 0
Great Bend 72 95 71 95 / 0 0 0 0
Salina 74 95 72 94 / 0 0 0 0
McPherson 73 94 70 92 / 0 0 0 0
Coffeyville 70 93 71 90 / 0 0 0 10
Chanute 71 94 71 90 / 0 0 0 10
Iola 71 93 71 91 / 0 0 0 10
Parsons-KPPF 71 93 71 90 / 0 0 0 10
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 7 PM CDT this evening for KSZ052-053-069>072-
093>096-098>100.
&&
$$
SHORT TERM...RM
LONG TERM...RM
AVIATION...ELM
FIRE WEATHER...RM