Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 08/09/20
Area Forecast Discussion
National Weather Service Quad Cities IA IL
610 PM CDT Sat Aug 8 2020
...00Z AVIATION UPDATE...
.SYNOPSIS...
Issued at 253 PM CDT Sat Aug 8 2020
A mix of clouds and full sunshine was the norm for much of eastern
Iowa, northwest Illinois and far northeast Missouri early this
afternoon with southwesterly flow ushering a very warm and humid
air mass across the area. Mid-level water vapor imagery showed an
EML present from far eastern Nebraska (sampled well on the 12z OAX
sounding) towards eastern Iowa, which was keeping us dry between
the elevated showers and storms in central Wisconsin and the
shortwave induced showers in eastern Missouri. As of 2 PM,
temperatures ranged from 77 in Macomb to 91 in Independence, with
dewpoints in the low to mid 70s making it feel more like the upper
80s to upper 90s!
&&
.SHORT TERM...(This Evening through Sunday Night)
ISSUED AT 253 PM CDT Sat Aug 8 2020
Key Messages:
1) Mainly dry through tonight, with storm chances returning Sunday.
2) Storms may be strong/severe Sunday PM.
This Evening and Tonight...
Convective allowing models continue the trend of poor handling of
current events, as activity has remained well to our northeast and
south. This is likely to continue through the evening and into early
tonight, especially as the warm air around 700 hPa continues to
build into the area. The only exception may be a brief window along
and north of I-80 this evening, where a shower or storm will be
possible where the atmosphere remains uncapped. Think most will be
dry though, with conditions remaining very warm and humid.
Overnight, there is a chance for a few showers and storms across
southeast Iowa, west central Illinois and northeast Missouri as the
slow moving shortwave in Missouri and a strengthening LLJ forces
convection. This may last through the morning before weakening with
the LLJ fading. It will be muggy as moisture levels continue to rise
at the surface, with lows only dropping near or into the low 70s.
Sunday...
Clouds from storms in Missouri and increasing moisture/WAA will
likely linger through the morning before decreasing in coverage as
drier air aloft mixes down. Once this happens, temperatures will
quickly warm as the very warm air mass (925-850 hPa temperatures of
~25 C) continues building into the area. This will result in
afternoon highs in the upper 80s to low 90s. When combined with
dewpoints in the low to mid 70s, heat indices will have no trouble
climbing into the upper 90s to near 100. A few spots may even reach
the low 100s, especially where there is higher agricultural
transpiration. For now, I did not go with a Heat Advisory as surface
winds around 15-20 MPH may help prevent pooling of dewpoints and
higher heat indices. However, I will pass this concern along to
subsequent shifts.
The next challenge of the day is chances of afternoon showers and
storms as guidance is back and forth on potential solutions. Several
CAMs including the ARW, the HRRR and even the new ECMWF are in
agreement of a piece of a morning MCS from central Minnesota riding
a MLCAPE gradient along the Mississippi River, which impacts much of
eastern Iowa by mid-afternoon. There is still a bit of uncertainty
in this, as there is potential for stronger WAA to help expand the
heat dome and keep convection further north into the Great Lakes, as
the NAM, GFS and CMC indicate. Regardless, this potential is enough
for me to keep at least chance POPs going mainly along and north of
I-80 through the early afternoon. SPC also has the same area
highlighted in a slight risk of severe thunderstorms, with the
primary threats being large hail and damaging winds with high
instability and steep lapse rates. Heavy rain will also be a threat
as storms interact with the extremely moisture rich air mass (PWATs
around 1.80-2.00").
Sunday Night...
Low confidence on this period as much of what happens will be
dependent on how the Sunday afternoon time frame evolves. However, a
cold front approaching from the northwest will likely lead to
additional showers and storms as it approaches the area from the
northwest late Sunday night. Temperatures will only fall into the
low 70s, which will combine with dewpoints around 70 to make for
another muggy night.
.LONG TERM...(Monday through Saturday)
ISSUED AT 253 PM CDT Sat Aug 8 2020
Monday
Main Points:
*Hot and humid conditions are expected with the highest confidence
south of highway 30. Forecast peak heat indices in this area are in
the mid 90s to around 100 F.
*Scattered storms are possible early in the morning and then again
late afternoon into Monday night. At this time, chances range
between 30-50% and are highest south of I-80 for the late afternoon
and early nighttime period.
Expecting another hot and humid day with highs in the mid 80s to
around 90 F, and dewpoints into the low to mid 70s. Leftover cloud
debris and earlier timing of an approaching weak cold front could
result in cooler conditions than currently forecast, especially for
areas along/north of highway 30.
A low amplitude trough will swing through the Upper Mississippi
Valley on Monday, with the 500mb height falls passing mainly to our
north through Minnesota and Wisconsin. This system will drag a cold
front through eastern Iowa and northwest Illinois, which could serve
as the mechanism for convective development during the afternoon or
evening. There is quite a bit of uncertainty on the timing of the
frontal passage and most likely period for convection.
Tuesday On
High pressure will bring near normal temps in the low to mid 80s and
a little lower humidity through the middle of the week. There are
periodic slight chances for storms, but latest model guidance
suggests chances may be confined to only the south in later updates.
The main message here is the majority of the CWA will likely stay
dry Tuesday and Wednesday.
For late week, models show remnant Southwest Monsoonal convection
and attendant mid-level vorticity maxima propagating into portions
of the Mid and Upper Mississippi Valley, as far north as central
Iowa and Illinois. Both the ECMWF and GFS eventually evolve this
upper disturbance into a slow moving cut-off low, lingering shower
and thunderstorm chances into next Saturday. The operational runs of
the ECMWF/GFS would favor cooler temps and wet conditions across our
south half on Friday and Saturday compared to the current model
blend forecast. Uttech
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday Evening)
ISSUED AT 610 PM CDT Sat Aug 8 2020
Scattered thunderstorms will likely remain well north and south of
the region overnight into Sunday morning. VFR conditions with
light south to southeast winds will thus prevail with a potential
for several hours of MVFR level fog toward sunrise, which is
included in the forecasts. Forecast models continue to depict the
development of low ceilings toward morning, which appears overdone
and have thus left out of the forecasts. A complex of thunderstorms
may move into eastern Iowa and northwest Illinois Sunday
afternoon and have advertised this with prob30 groupings at DBQ,
CID and MLI.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...Speck
SHORT TERM...Speck
LONG TERM...Uttech
AVIATION...Sheets
Area Forecast Discussion
National Weather Service Wichita KS
614 PM CDT Sat Aug 8 2020
.SHORT TERM...(This evening through Tuesday morning)
Issued at 301 PM CDT Sat Aug 8 2020
Warm southerly breezes dominate the weather pattern this afternoon,
as SW downslope flow leads to above normal temperatures. There is
one minor "fly in the ointment", as a subtle meso induced vort
center (MCV) over south central KS continues to drift NE this
afternoon. As this MCV swings northeast, the airmass for areas west
of I-135 may become uncapped by around 00z just ahead of this MCV.
As the atmosphere becomes uncapped, RAP Bufkit soundings suggest
parcels will be very elevated with cloud bases around 10k ft. So
there is a slim chance of an isolated rogue shower/storm developing
as this MCV lifts NE and parcels become uncapped. Think just some
elevated TCU will be the main concern, or possibly some virga from
the high bases. So for now, will go with a "silent 14 pop" for this
chance.
As the late evening progresses, mid level moisture transport and
warm advection increases for areas along and north of I-70 and into
NE KS. This warm advection will also increase the mid level temps to
around +14-15 C. at 700h. So think any overnight shower/storm
chances will be limited to areas north of the forecast area, as the
warmer temps aloft keep storms from developing. Again a rogue
shower/storm may develop along I-70, but for now plan on going with
a "silent" 14 pop.
Another warm day is expected on Sun, as south-southwest flow leads to
good downslope conditions, with max temps again climbing into the
mid to upper 90s. For Sunday afternoon, a weak frontal boundary will
push into north central KS, with the warm elevated mixed layer (EML)
in place south of the front, keeping convection from developing.
Afternoon heating and weak convergence along the front may lead to a
few showers/storms developing across central KS for late Sun
afternoon or Sun evening, as the front sags further south. The main
concern with any storm that develops will be some gusty downburst
winds with the storms, due to marginal bulk shear values around 20-
25 kts and inverted-V wind profiles, with elevated storm bases.
The chance of showers and thunderstorms increases on Monday, as the
diffuse frontal boundary and mid level baroclinic zone sags south
across the forecast area for Mon afternoon/Mon evening. Expect
showers and thunderstorms to develop along this diffuse boundary, as
a shortwave in the zonal flow moves out of the Rockies and into the
plains. The shear instability combination suggests a few strong to
marginally severe storms may occur for Mon evening, with activity
forming into an eastward forward propagating complex of storms for
late Mon night into early on Tue.
Ketcham
.LONG TERM...(Tuesday through Saturday)
Issued at 301 PM CDT Sat Aug 8 2020
The unsettled pattern looks to continue for Tue through Thu, as the
zonal flow leads to weak impulses in the flow scooting across the
area, leading to diurnally driven storms chances and then overnight
and early morning storm chances. The periodic storm chances will
lead to temperatures staying near seasonal averages for most of the
work week.
Ketcham
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 612 PM CDT Sat Aug 8 2020
VFR conditions will prevail throughout the TAF package. A few AC
and CI are migrating across portions of SC KS at issuance.
Isolated RW is possible but mainly seeing virga from this cloud
deck. Some pockets of wind shear is forecast for all sites around
the 06Z time frame. Mainly in speed sheer up to 40kts as you
climb. Otherwise, a repeat on Sunday is forecast with storng gusty
south winds.
&&
.PRELIMINARY POINT TEMPS/POPS...
Wichita-KICT 76 99 75 95 / 10 10 10 20
Hutchinson 75 99 73 94 / 10 10 20 20
Newton 75 97 73 94 / 10 10 20 20
ElDorado 75 96 75 94 / 10 10 10 20
Winfield-KWLD 76 97 75 95 / 10 10 10 20
Russell 74 99 70 92 / 10 10 20 20
Great Bend 73 99 70 92 / 10 10 20 20
Salina 76 100 73 95 / 10 10 20 20
McPherson 75 99 72 93 / 10 10 20 20
Coffeyville 76 96 76 95 / 10 10 10 20
Chanute 75 96 76 95 / 0 10 10 30
Iola 75 96 75 95 / 0 10 10 30
Parsons-KPPF 77 96 76 95 / 0 10 10 20
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...Ketcham
LONG TERM...Ketcham
AVIATION...CWH
Area Forecast Discussion
National Weather Service North Platte NE
638 PM CDT Sat Aug 8 2020
.SHORT TERM...(This evening through Sunday night)
Issued at 407 PM CDT Sat Aug 8 2020
Near term concerns revolve around the potential for scattered severe
thunderstorms later this afternoon and evening. Surface analysis
depicts a frontal boundary set up roughly along an Imperial to
Thedford to Bassett line. South of this front, a warm and humid
airmass is in place with dew points in the upper 60s to low 70s and
air temperatures in the upper 80s to low 90s. This is leading to a
plume of high MLCAPE with values of 3000-4000 j/kg noted on SPC
mesoanalysis. Taking a look at the 20z special sounding from LBF,
very steep mid-level lapse rates are already in place helping drive
the strong instability. At the same time, dry air in the low-levels
in addition to very warm h85 temperatures are also leading to strong
inhibition across the area. General thoughts are as temperatures
continue to increase coincident with moisture quality remaining the
same if not slightly increasing as well, inhibition will diminish
through the afternoon hours. While the capping inversion may never
completely erode, a modest shortwave combined with h5 height falls
and increasing convergence along the boundary will help spark off
thunderstorms by late this afternoon. This activity will persist
into the evening hours aided by a strengthening LLJ. Given such
steep mid-level lapse rates and 0-6km BWD values of 25 to 30 knots,
multicell clusters with some supercell structures will be the
predominant storm mode capable of large hail, some up to the size of
golf balls, and damaging wind gusts up to 80 mph, as DCAPE values
approach 1800 j/kg, will be the main threats. Given the orientation
of shear vectors compared to the surface boundary, any discrete
storm will be short lived as storms grow upscale quickly and
transition into a mostly damaging wind gust threat. The threat for
training storms will also lead to locally heavy rainfall with PWAT
values in the 1.00-1.25" range expected in the pre-convective
environment. Rainfall amounts of 0.50-1.00" are likely with
localized amounts of up to 2.00" possible in areas that see multiple
rounds of thunderstorms. Expecting the bulk of the thunderstorm
activity to exit the area by early morning Sunday as the LLJ begins
to veer, focusing east of the area. Lows will remain mild overnight
across the east, only falling into the mid to upper 60s meanwhile
falling into the upper 50s across the west.
Surface boundary remains anchored across the area into Sunday,
providing another opportunity for isolated showers and
thunderstorms. While forcing for ascent will not be as strong as
what was seen Saturday, the environment will still be supportive for
strong to severe thunderstorms should any develop. MLCAPE values
will climb into 3000-4000 j/kg range for areas east of Highway 83
with 0-6km BWD values in excess of 30 knots. Storms will likely be
elevated, posing the threat for large hail and damaging wind gusts.
The greatest uncertainty will be if a storm develops given lack of
upper-level support. The extended HRRR and NAM Nest both advertise
storms developing, so would not be surprised to see the SPC extend
the Marginal further southwest out of strictly only north central
Nebraska. Another warm day is expected with daytime highs generally
in the 90s with upper 90s expected south of Highway 92. Heat index
values are expected to fall short of criteria, however, given drier
air in place.
.LONG TERM...(Monday through Saturday)
Issued at 407 PM CDT Sat Aug 8 2020
Beginning 12z Monday. Period begins with relative zonal flow and
modest high pressure along the Gulf coast and a strong mid-level
disturbance approaching Hudson Bay. The frontal boundary from Sunday
will settle south of the area before stalling, providing the focus
for renewed thunderstorm development on Monday as a weak mid-level
disturbance moves across the southern to central Plains. Some
discrepancies regarding northward extent of any rain and
thunderstorms associated with this activity. The GFS limits this to
areas southeast of a North Platte to Broken Bow line, thus keeping
most of the area dry. Meanwhile the ECMWF suggests this activity
making it as far northwest as a Big Springs to Mullen to Spencer
line, thus splitting the CWA nearly in half suggesting dry northwest
and PoPs southeast. Will hedge towards the more aggressive output
and maintain PoPs across much of the area for now. As weak high
pressure works in to the area, mostly cloudy skies will be prevalent
helping keep temperatures cool with highs only reaching the 70s to
low 80s. Beyond Monday, a steady stream of mid-level energy will
traverse the central Plains bringing near daily chances for rain and
thunderstorms to the area through the following weekend. Southerly
low-level flow will largely be uninterrupted through that time
frame, allowing for the humid airmass to remain in place. Predicting
small-scale features at length is difficult and for that reason,
confidence in severe potential for any one day is low confidence.
That said, mid-level flow appears to be strongest on Tuesday and
possibly Friday so will be watching those days the closest though no
one day can be completely ruled out at this time. After a cooler day
Monday, temperatures will generally climb to near to slightly above
normal values for mid-August with a frontal boundary potentially
bringing another cooldown sometime during the weekend.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 637 PM CDT Sat Aug 8 2020
The greatest threat for thunderstorms will be over the next 2 to 4
hours at the KLBF and KVTN terminals. Any thunderstorms which do
impact the KLBF and KVTN terminals, have the potential to produce
wind gusts over 40 KTS with ceilings around 4000 FT AGL. The
threat for thunderstorms will diminish quickly after 05z with a
gradual clearing of sky cover overnight. Skies will be mostly
clear on Sunday.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...Jurgensen
LONG TERM...Jurgensen
AVIATION...Buttler
Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
906 PM CDT Sat Aug 8 2020
.UPDATE...
906 PM CDT
Overall the forecast remains on track this evening. Although
there continues to be a complex of thunderstorms moving east
across west central Wisconsin this evening, these are expected to
remain north of the local area. Conditions are not overly
favorable for additional development along any potential outflow
boundaries that try to push south into northern Illinois
associated with the ongoing convection. Thus, have opted to
remove any remaining precip mention along the WI/IL border. Have
also increased sky cover slightly across our far southern zones to
account for the increased cloudiness associated with a
disturbance moving across central and southern Illinois. While a
few spotty showers have attempted to develop into central
Illinois earlier this evening, they struggled to maintain
intensity and have since dissipated, so will continue to keep
things dry across our southern zones.
Petr
&&
.SHORT TERM...
302 PM CDT
Through Sunday night...
Convective trends pose the primary item of interest for the near
term and unfortunately there is considerable uncertainty with the
timing and location of activity that may develop. In general the
coverage would appear to be rather minimal given the degree of low
level inhibition for most of the period, but steep midlevel lapse
rates, periodic upper level shortwaves, and outflow boundaries from
nearby convection all could provide enough support to get at least a
few parcels to their LFC. Overall trends appear to gradually
increase through the period, especially later Sunday into Sunday
night but even more so into the early extended.
For this evening the area of focus for thunderstorms would be toward
the WI line ahead of the dissipating activity presently moving
through, with showers also possible in our far south associated with
the weak circulation that moved out of Missouri earlier in the day.
Conditions Sunday are not looking to be quite as hot and humid as
had been expected earlier in the week, but heat indices should
still reach the mid 90s in most locations.
Lenning
&&
.LONG TERM...
311 PM CDT
Monday through Saturday...
The forecast for Monday will be somewhat dependent on how things
ultimately evolve Sunday night. While there remains some model
variability, there exists the potential for an MCS to move
through the area some time Sunday night into Monday morning. If
this does occur, once it moves through, winds are expected to
turn southwesterly during the day which will help to advect
additional moisture and warm air into the region. Some lingering
high clouds from lingering morning convection could limit some of
the surface heating during the day, but overall still expect a hot
and muggy afternoon with heat indices in the upper 90s to near
100 degrees.
The cold front will begin to make its way through the area Monday
afternoon and evening. Instability is expected rebound ahead of
the front in the afternoon. This combined with steep mid-level
lapse rates and convergence along the front providing a source of
lift would suggest the potential for strong to marginally severe
storms. Although there is some model variability, shear in the
15-25kt range would also be sufficient for at least some
marginally severe hail.
Looking beyond Monday, the front may stall out somewhere near our
southern zones or just south of the forecast area. Will continue
to hold onto some chance PoPs Tuesday and again Wednesday for
areas mainly south of I-80 to account for additional precip
development near the boundary. Off and on precip chances continue
through the remainder of the extended due to uncertainties with
regard to timing of any convective complexes that develop and
move across the upper midwest. Highs will be more seasonable in
the 80s.
Petr
&&
.AVIATION...
For the 00Z TAFs...
Only real aviation forecast concern through the next 24-30 hours
is the low potential for thunderstorms. This potential appears to
increase later Sunday night, just beyond the end of this TAF
period.
Early evening surface analysis depicts high pressure centered off
to the east of the region across the lower Great Lakes. Primary
surface low pressure center was well to the north across the
Canadian prairie provinces, with a slow moving cold front trailing
from Minnesota to the High Plains. Ahead of this front, southerly
low level winds have brought a warmer and more humid air mass into
the Midwest. With this warm/humid air mass comes considerable
conditional instability, though warm temperatures in the 850-700
mb layer continue to provide capping/convective inhibition which
will require organized low level convergence to break through.
Therefore, absent of some strong organized outflow boundary or an
MCS propagating into the forecast area, the potential for
organized convection appears rather minimal through much of the
period. In the near term, a strong convective cluster over
southeast Minnesota and its outflow boundary along its southern
periphery is worth monitoring. Deep layer flow and the presence of
the cap to its south would support more of an eastward propagation
of the storms with weakening expected after dark, with the outflow
unlikely to reach the area until the pre-dawn hours of early
Sunday if it gets here it all. Convection downstate in the
vicinity of KSTL should move southeast, and should not be a factor
for our terminals.
Sunday looks to be very similar to today, warm mid-level temps
providing capping once again. Some CAM guidance (18Z runs of the
HRRR and HRRRx) indicate the potential for thunderstorms to
develop across northern IA during the day Sunday, and approach the
terminals early Sunday evening, while other guidance is slower
with convective threat this far east. Will maintain dry TAFs
through Sunday evening at this point, with greater potential
likely beyond current TAFs.
Otherwise, south winds 190-210 deg or so expected with some gusts
near 20 kts during the day and easing diurnally in the evenings.
VFR cu/stratocu possible, though forecast soundings would suggest
perhaps less cu Sunday than there was today.
Ratzer
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...None.
IN...None.
LM...None.
&&
$$
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Area Forecast Discussion
National Weather Service Pocatello ID
915 PM MDT Sat Aug 8 2020
.UPDATE...No updates to the forecast this evening other than to
expire the RED FLAG WARNING for the Snake Plain and portions of
the central mountains. We do expect some lingering mid and higher
level clouds, along with smaller pockets of smoke for fires
across the Magic Valley and the central mountains. Keyes
&&
.PREV DISCUSSION... /issued 157 PM MDT Sat Aug 8 2020/
SHORT TERM...Tonight through Monday night.
Minor impacts with main one to be breezy conditions this evening
and again Sunday afternoon. Winds not expected to be quite as
strong Monday afternoon. Generally 20 to 30 mph gusts expected
this evening and again Sunday afternoon mainly in Snake River
Plain. No precipitation is expected in the short term period with
high temperatures right around or only slightly above seasonal
normal for early August.
GK
LONG TERM...Tuesday through Saturday.
Expect a little moisture to return on southwest flow aloft ahead
of a weak Pacific trof and a slight chance of thunderstorms to
the southern and eastern highlands Tuesday through Friday.
Wednesday should have the most coverage with very little for the
most part. Precipitation not expected to be very plentiful.
Temperatures will remain above normal thorugh the long term
period.
GK
AVIATION...
Gorgeous VFR conditions continue this weekend with diurnally breezy
afternoon winds really the only element to be aware of, especially
for the Snake Plain terminals and perhaps KDIJ. This should be the
case through Tue (with those winds relaxing/trending a bit lower
each day), with otherwise high confidence in no impacts to aviation.
Winds should continue their daily afternoon shift from SE to WSW at
KSUN with a slight crosswind, and we continue to include this in the
TAF via 2 afternoon FM groups, with timing based on the MAV/MET/HRRR
consensus and previous day`s timing of the shift. The other element
we are watching for KSUN is potential smoke advecting into the Wood
River Valley from the Phillips Creek Fire on a predominant westerly
flow just off the sfc. DEQ monitoring stations are few/far between,
but the Ketchum station currently rates air quality as GOOD/GREEN,
and no reductions in vsby have been noted at KSUN so far. The HRRR
smoke model does suggest a better smoke plume streaming eastward
across central Blaine, far southern Custer, and central Butte
counties this afternoon, although confidence is low and it remains
unclear whether much of this will affect the sfc (valleys). Will
continue to monitor...no other terminals look to be impacted at this
time. Increased troughing across the PacNW may bring t-storms back
to the forecast for some areas by Wed afternoon. - KSmith
FIRE WEATHER...
No major changes in our thinking for gusty winds/low RH values this
afternoon, and a Red Flag Warning remains in effect until 9 PM for
zones 410/476. Similar near-critical to critical conditions are
expected over NE portions of Zone 425 as well over the Craters of
the Moon region, but coverage of this still doesn`t quite cover
enough of the overall zone to include them in the warning (RHs
there, winds not so much). Will continue to highlight this in the
FWF. RHs hold a few percent more moist (generally not quite
critical) Sun with a similarly breezy afternoon expected. RHs will
gradually dry out again Mon/Tues, although winds appear to lean
light with no organized systems directly impacting the region.
Increased troughing moving inland across the PacNW may bring t-
storms back to the forecast by Wed afternoon for most of our mntn
regions. The GFS/ECMWF/Canadian still offer a bit of a spread on how
strong/amplified this trough will be. Isolated coverage still
appears the way to go for the rest of the week, and increased upper-
level support/tighter pressure gradient may bring some wind concerns
back to the mix as well. Any t-storms at this time appear to be
pretty dry with low CWRs. - KSmith
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Area Forecast Discussion
National Weather Service Springfield MO
623 PM CDT Sat Aug 8 2020
...Updated for 00Z Aviation Discussion...
.SHORT TERM...(This evening through Sunday)
Issued at 144 PM CDT Sat Aug 8 2020
No real forecasting concerns this evening with a decent enough cap
in place and plenty of dry air distributed within the troposphere.
The once exception could be across the eastern Ozarks, namely east
of Highway 63, where the cap is less prevalent and mid-level
moisture is a hint better. There also appears to be a lingering
lobe of vorticity at 500 mb near St. Louis, perhaps coinciding
with a remnant MCV that moved through the region earlier this
morning. Some convective-allowing models (CAMs) suggest a period
of heavy rainfall overnight along the Mississippi River where the
RAP indicates a decent axis of moisture convergence below
relatively weak upper-level flow. As the low-level jet noses
across central Missouri into the mid-Mississippi Valley tonight,
heavy rainfall may be of concern just east of our CWA. Overnight
temperatures will only cool into the low-to-mid 70s.
For Sunday, the main forecasting concern will be heat. With 850-mb
temperatures around 22-24 C mixing down to the surface,
low-to-mid 90s seems like a safe bet for the region, and with dew
points in the 70s across far western Missouri and eastern Kansas,
heat index values will push into the triple digits. No
thunderstorm activity is anticipated Sunday afternoon with short-
term guidance maintaining a stout cap.
.LONG TERM...(Monday through Saturday)
Issued at 144 PM CDT Sat Aug 8 2020
Next week continues to look like a wet and unsettled period.
Showers and thunderstorms may return to the region by Monday
afternoon as a shortwave digs toward the western Great Lakes and
drags a weak cold front along the I-70 corridor. This front could
be the focus for some scattered thunderstorm activity from Ft.
Scott, Kansas to Salem, Missouri. South of this front,
temperatures will again be hot with highs in the mid 90s and heat
index values nearing triple digits.
Tuesday through Saturday may feature numerous chances for
widespread rainfall across southeast Kansas and southwest
Missouri as the surface front remains draped across our CWA
beneath weak upper-level flow. With several shortwaves progged to
eject out of the Central Plains, and the low-level jet coming and
going throughout the week, confidence is increasing that the
region will see multiple rounds of showers and thunderstorms.
Flooding concerns may begin to ramp up by mid-week wherever
multiple rounds of rain occur; and there may be some flash
flooding concerns as well given the weak flow aloft and humid air
mass in place.
Temperatures next week will feature daily highs near 90 and
overnight lows near 70.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 623 PM CDT Sat Aug 8 2020
VFR flight conditions will prevail through the TAF period.
Southerly winds will remain in the 10 to 15 knot range for the
most part, with some gusts to 20 to 25 knots possible after 15Z
Sunday.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Albano
LONG TERM...Albano
AVIATION...Raberding