Forecast Discussions mentioning any of
"ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 06/14/21
Area Forecast Discussion
National Weather Service Denver/Boulder CO
911 PM MDT Sun Jun 13 2021
.UPDATE...
Issued at 858 PM MDT Sun Jun 13 2021
Well, that was a bit unexpected. A couple convective cells finally
were able to break through the cap this afternoon, which led to
almost two dozen large hail reports across the I-25 corridor
today. Thunderstorms have gradually weakened this evening, though
there are still a few showers and storms around. The cluster of
cells over Morgan and Logan counties have produced some strong
outflow wind gusts over the past hour, and we could see briefly
gusty northeast winds for the Denver metro here in the next hour
or so. These winds should diminish by midnight or so as the near
surface stable layer deepens and convection wanes.
Otherwise, the rest of the night should be fairly quiet, with
clearing skies. Lows tonight will fall into the low 60s for most
of the plains, before hot temperatures return again tomorrow. I`ve
attempted to make some adjustments to the PoP and T/Td fields to
catch up to observations, but the forecast for the rest of the
night is largely unchanged.
&&
.SHORT TERM...(This evening through Monday)
Issued at 255 PM MDT Sun Jun 13 2021
We`ve had a few puffs of convection in the higher foothills on the
upslope wind convergence line, but this has generated clouds that
will further hinder surface based convection in areas just east of
the mountains and this initial batch has settled down. There is
still potential for more of this, but it will likely produce
similar results. The surface moisture layer is beginning to mix
out in the area east of the mountains. ACARS soundings verify the
expected slight warming in the 700-500 mb layer as well. There`s
no change to the expectation that isolated weak convection is all
we`ll get there. Of more interest will be the fate of the storms
currently north of Cheyenne. They are creeping into a slightly
capped environment, but if they`re able to survive they could
eventually work southeastward into northeastern Colorado. The
environment remains short on shear, especially this afternoon, but
with enough CAPE for a low severe threat. Wind still looks like
the main threat though a strong updraft could produce large hail.
The greater threat is still convection moving from further north
in Nebraska and clipping the northeast corner later tonight. There
may be a sweet spot for supercell mode or strong multicells in the
Nebraska panhandle this evening, but this will likely be
transitioning to an outflow driven complex and decaying by the
time it gets to Colorado. We`ll hang on to some low PoPs late into
the night for this possibility.
Monday looks similar to today in general, but there is slight
warming and drying which should make it even harder to get storms.
There`s still some CAPE over the plains but it should be capped.
Model soundings and statistical guidance suggest another 2 to 4
degrees F of warming from today, which will put the warmer areas
near 100.
.LONG TERM...(Monday night through Sunday)
Issued at 255 PM MDT Sun Jun 13 2021
Upper ridging will stay centered around the Four Corners Monday
night through Wednesday night. The QG Omega fields have benign
synoptic scale energy in place all five periods. The flow aloft
remains pretty weak. The low level winds will adhere to the normal
diurnal wind patterns through Wednesday night.
Concerning moisture, the surface dew point, precipitable water and
QPF fields all indicated there will still be some in place, at
least over most of the plains. Will keep the limited late day pops
going.
Looking at the heat, the thickness, 850 mb and 700 mb temperatures
fields all continue to show record temperatures, certainly for
Denver, on both Tuesday and Wednesday. The MOS Guidances show a 100
degree (or more) reading in Denver on Tuesday.
For the later days, Thursday through Sunday, upper ridging will
continue in control of the CWA`s weather, however the ridge center
will migrate south and west somewhat on Friday and Saturday.
Thursday, possibly, could have one more day of record heat. On
Sunday and Sunday night, the medium range model solutions diverge,
with the ECMWF showing upper troughing sliding eastward north of the
state. The GFS keeps the ridging entrenched over us. Both models
relax the excessive heat a bit, for next weekend.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 858 PM MDT Sun Jun 13 2021
VFR conditions through Monday evening. Outflow boundary is
currently approaching DEN from the northeast and should arrive
just prior to 04z, with NE gusts up to 30kt or so. Less
confidence this boundary makes it to BJC or APA. Drainage flow is
expected to re-establish later this evening, with winds turning
back to the east or southeast by Monday afternoon. There is an
outside chance for a thunderstorm or two tomorrow, but confidence
is very low in that scenario.
&&
.FIRE WEATHER...
Issued at 255 PM MDT Sun Jun 13 2021
We will have near record heat through Thursday across the area.
Humidities will be very low west of the Front Range, and these
will spread east of the mountains by Wednesday. Fuels will
continue to dry, so fire danger will be increasing. In general,
strong winds are not expected, though there will be breezy
conditions in the afternoon in some areas.
&&
.HYDROLOGY...
Issued at 255 PM MDT Sun Jun 13 2021
Isolated thunderstorms over the plains tonight and Monday night
could produce very localized heavy rain, but the flood threat is
low. Elsewhere a flooding threat is not anticipated this week.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE...Hiris
SHORT TERM...Gimmestad
LONG TERM...RJK
AVIATION...Hiris
FIRE WEATHER...Gimmestad
HYDROLOGY...Gimmestad
Area Forecast Discussion
National Weather Service Houston/Galveston TX
1001 PM CDT Sun Jun 13 2021
.DISCUSSION...
Some locations across the area saw their first 100 degree readings
of the summer. Hot, humid conditions with light winds anticipated
again tomorrow. Heat indices may approach advsy criteria for a
short time period Monday...with the more favorable conditions
across the southern part of the area and where a weak seabreeze
might come into play. That said, it appears that same general
location might be where the better chances of sct tstms could be.
We`ll let the next shift or two take a look at things, but heat
messaging will remain the same - advsy or not.
In the short term, monitoring thin line of convection stretching
across La. It`s moving sswly at a decent clip. Based on aircraft
soundings, capping has set back up closer to the metro area with
the loss of heating. So precip should be on the weakening trend,
but given its forward speed, went ahead and added some POPs into
the fcst for easter & southern parts of the region during the
overnight hours. Some areas could see a brief 20mph gust or two
as the remnant outflow passes. Nudged temps up a degree or two for
Monday as well. 47
&&
.PREV DISCUSSION... /ISSUED 642 PM CDT Sun Jun 13 2021/
AVIATION [00Z TAF ISSUANCE]...
Mostly VFR conditions expected tonight with light and VRB winds.
Winds will turn N-NW at 5-8 KTS Monday. An upper level trough is
progged to set up to our east Monday, allowing for a bit more
SH/TS development across portions of the CWA. The chance for SH
will possibly start along the coastal locations early in the
morning and expanding northward as the morning progresses. By late
morning into early afternoon, development of TS is expected as
heating ramps up. These SH/TS will be capable of producing strong
gusty winds, brief periods of heavy rain with reduced visibility,
and frequent lightning. Some chop can occur in and around SH/TS.
Activity is expected to dissipate gradually during the evening and
early night hours with the loss of heating, but a few lingering
storms could still move/develop across some locations a few hours
past that. At this time, will keep a general timeframe with SH/TS
until models become a little more in agreement with timing and
placement before adding the TEMPOs. 24
&&
.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 77 95 75 95 73 / 10 20 10 20 10
Houston (IAH) 79 98 77 95 75 / 30 40 30 30 20
Galveston (GLS) 81 92 80 92 80 / 20 30 20 20 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$