Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/01/23
Area Forecast Discussion
National Weather Service Dodge City KS
607 PM CDT Tue Oct 31 2023
...Updated for aviation discussion...
.KEY MESSAGES...
Issued at 202 PM CDT Tue Oct 31 2023
- Rapid warm-up from today into tomorrow, with temperatures
increasing further into the 70s by Friday.
- No precipitation chances throughout the entire period.
&&
.SHORT TERM...(This evening through Wednesday night)
Issued at 202 PM CDT Tue Oct 31 2023
Midday water vapor satellite imagery and RAP upper air analysis
depicts a longwave trough extending from the Rockies through the
east coast, with a weak longwave ridge over the west coast and
Intermountain West. These features will move little throughout
the short term period while a strong vorticity max embedded within
the trough, currently centered near the southern edge of Lake
Michigan, rapidly shifts east. At the surface, high pressure will
slide from the northern/central plains south-southeastward to the
ArkLaTex region by tomorrow afternoon in the wake of the strong
upper level vorticity lobe. This will allow winds to switch from
northerly today to south or south-southwesterly tomorrow, and
this newfound downsloping wind component will facilitate a
significant warm up from the 40s today into the upper 50s to mid
60s Wednesday afternoon. Given synoptic-scale subsidence ahead of
the upper level ridge and little to no moisture content (PWAT of
0.19 inches off the 12Z DDC raob), the probability of any
precipitation anywhere across southwest KS is 0%.
.LONG TERM...(Thursday through Tuesday)
Issued at 202 PM CDT Tue Oct 31 2023
Quiet, dry weather will continue through the long term period, as
medium range ensembles agree the upper level ridge out west will
break down during the day Thursday, resulting in the upper level
flow becoming largely zonal through at least the weekend.
Temperatures will continue to warm Thursday and Friday, with
highs in the mid/upper 60s Thursday likely increasing into the
low/mid 70s Friday for much of the area as probability of
temperatures exceeding 70 is 90-100% along and west of US-283.
Over the weekend, ensembles indicate 500-mb heights will
gradually decrease, and temperatures will follow suit. Probability
of exceeding 70 degrees drops to 60-80% on Saturday, and 30-60%
Sunday.
Sunday night, ensembles suggest a modest upper level shortwave
trough will eject into the central plains, sending a dry cold
front through southwest KS. CAA in the wake of this front will
drop temperatures closer to normal (low/mid 60s) as probability of
temperatures exceeding 70 diminish to 10-20% on Monday and then 0%
on Tuesday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 600 PM CDT Tue Oct 31 2023
A surface trough will develop across the high plains through the
period. This will result in light winds gradually becoming south
to southwest at 8-15 kts during the 06-15z time frame. VFR
conditions will prevail.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 25 64 29 66 / 0 0 0 0
GCK 24 64 26 66 / 0 0 0 0
EHA 26 66 30 67 / 0 0 0 0
LBL 24 65 25 66 / 0 0 0 0
HYS 22 62 27 63 / 0 0 0 0
P28 23 58 30 63 / 0 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Springer
LONG TERM...Springer
AVIATION...Finch
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
644 PM CDT Tue Oct 31 2023
.DISCUSSION...(This evening through Tuesday)
Issued at 211 PM CDT Tue Oct 31 2023
KEY MESSAGES:
- Becoming a bit warmer later this week, with the return of
precipitation chances this weekend.
The potent upper low that brought 2-4 inches over much of eastern MN
and WI continues to track away and is now centered over
Chicago/Milwaukee areas. Some stratocu remains in bands confined to
western MN and western WI, with a nice dry slot across eastern MN.
Temperatures have warmed to about what was expected, despite the
fresh snowpack. Clearing skies this evening and light winds should
allow temperatures to drop into the teens to low 20s. Increasing
clouds late should steady out the drop and temps could rise slightly
toward morning.
Northwest upper flow will prevail into late week but southerly low
level flow will help moderate temperatures back into the 40s, and
possibly 50, by Friday. The pattern will flatten more this weekend
into next week with several disturbances in the form of sheared
pieces of energy tracking east across the northern CONUS. One
stronger wave could bring the best chance for precip Sunday night
and Monday. Low chances for precipitation are maintained this period,
with low confidence on the details or timing of each.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 635 PM CDT Tue Oct 31 2023
Models have handled MVFR cigs in western MN very poorly today (they
should have disappeared long ago according to most models) and think
some of this moisture will follow the surface ridge axis east
tonight. Looking at RAP forecast soundings for STC, MSP, RNH, and
EAU, you see a brief period at each field where the RAP shows
moisture around around 2k feet moving through. For now, added tempos
to cover this threat. The rest of the TAF period remains unchanged,
with a shortwave dropping down from Canada bringing cigs down to
between 7k and 12k feet to go along with more south to southwest
winds for Wednesday.
KMSP...The RAP shows potential for MVFR cigs between 7z and 10z as
the ridge axis moves through, bringing moisture associated with the
MVFR cigs out in western MN through as well. That`s the reason for
the TEMPO MVFR cigs between 7z and 10z. No changes to the rest of the
TAF.
/OUTLOOK FOR KMSP/
Thu...VFR. Wind W 5-10 kts.
Fri...VFR. Wind S 5-10 kts becoming N.
Sat...VFR. Chc MVFR/-SHRA Wind NE 5-10 kts.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.
&&
$$
DISCUSSION...Borghoff
AVIATION...MPG
Area Forecast Discussion
National Weather Service Morristown TN
928 PM EDT Tue Oct 31 2023
...New UPDATE...
.UPDATE...
Issued at 920 PM EDT Tue Oct 31 2023
...Freeze Warning Remains in Effect for Tonight...
A scattered to broken deck of 4-5kft of clouds remain over the far
eastern Mountains. HREF and latest HRRR shows this area of
moisture slowly eroding but another shear axis is moving
southeast across middle Tennessee.
This shear axis has another band scattered to broken of 4-5kft
cloud cover. However, due to downslope winds into the valley, high
resolution model and HREF show this moisture diminishing as it
moves into the valley. The moisture will keep the eastern
mountains generally mostly cloudy through early morning.
Cold air advection will continue to pull unseasonably cold
conditions into the region with temperatures falling into the 20s
most locations by daybreak. Will maintain current freeze warning.
&&
.SHORT TERM...
(This evening through Wednesday)
Issued at 305 PM EDT Tue Oct 31 2023
Key Messages:
1. Coldest Halloween since 2014.
2. Near-record lows forecast tonight at Tri-Cities and Oak Ridge.
3. Very dry on Wednesday. Afternoon RH values of 25-35 percent
expected.
Discussion:
Clouds continue to butt up against the mountains this afternoon
as low level moisture lingers behind a departing cold front. These
have been slowly eroding, but expect they will not totally clear
out until later tonight when another front swings through the
area. Not expecting much of any precipitation chances with this,
although it wouldn`t be out of the question to see a stray shower
or two get squeezed out across the higher terrain of our Virginia
counties or perhaps the far northeast TN mountains in the
strengthening northwest H85 flow. But will not carry any PoPs for
that as upper support isn`t that favorable, and I think they`ll be
isolated at best.
Otherwise, the main forecast item of note is going to be
temperatures. This is the coldest Halloween since 2014 pretty much
area wide, and temperatures will begin to fall rapidly this
evening as trick-or-treating festivities begin. Expect
temperatures firmly in the 40s for much of the lower elevations of
the CWA where the majority of the population lives. And it will be
a little breezy, especially down towards Chattanooga.
For tonight, forecast lows are expected to be near record
territory for the Tri-Cities area and perhaps Oak Ridge.
Chattanooga and Knoxville are forecast to be more in the range of
+5 degrees higher than the record lows so I think those are safe.
See the climatology section below for more specifics on the temp
records. Given the expected temperatures, will go ahead and keep
the freeze warning in place. Despite winds remaining elevated
tonight, forecast values deep into the 20s seem highly likely so
the freeze warning seems necessary.
Tomorrow will be cool, with highs in the 40s to maybe low 50s.
Nothing close to records. High pressure will build in from the
west so winds shouldn`t be as gusty tomorrow as they have been in
places today. May need to issue another SPS for elevated fire
danger as afternoon RH values will fall off into the 25-35 percent
range for valley and mid-slope locations. But with winds not
expected to be as high as today, which was still well below any
red flag criteria, decided against issuing one with the afternoon
package.
&&
.LONG TERM...
(Wednesday night through next Tuesday)
Issued at 305 PM EDT Tue Oct 31 2023
Key Messages:
1. Below freezing temperatures Wednesday night, 15 degrees below
normal. Near record to record lows for some.
2. Dry, with a slow warming trend from Thursday and into the
Weekend.
3. Next chance of rain early next week.
Wednesday night through the weekend...
Wednesday night will be another very cold night with temperatures
ranging from the low to upper 20s, which is around 15 degrees below
normal. Record low expected at TRI. The forecast low on Wednesday
night/Thursday morning is 23 and the record is 24.
Thursday through Friday feature high pressure in place to our east
with mostly zonal flow in place. Temperatures will slowly climb
during this time with max temps near normal by Friday, but still
slightly below. The dry air in place will allow for afternoon low
min RH on both days but with light winds in place, which will help
to lessen the fire weather concern.
On Saturday, high pressure shifts further east and the flow becomes
more southerly in the low to mid levels. This allows temps to
finally return to normal. An upper level trough swings across the
Great Lakes on Sunday which allows the 850mb jet to strengthen due
to a tightening pressure gradient. So while winds become more
breezy, RH values won`t be as low due to the southwesterly flow,
allowing higher dewpoints to spread in across our area.
Timing is still uncertain, but models still showing a system in the
Monday/Tuesday timeframe that will hopefully provide us with much
needed rainfall. Depending on the track of the low, we could also
see some breezy winds, especially across the mountains, due to a
moderately strong 850mb jet. Will keep a close eye on this system.
&&
.AVIATION...
(00Z TAFS)
Issued at 708 PM EDT Tue Oct 31 2023
VFR conditions are expected at all TAF sites through the forecast
period. Winds will remain breezy out of the west to northwest
gusting up to 20 knots.
A scattered to broken deck of 4-5kft of clouds remain over or just
east of TRI and TYS. HREF and latest HRRR shows this area of
moisture slowly eroding the next couple of hours but another shear
axis is moving southeast across middle Tennessee.
This shear axis has another band scattered to broken of 4-5kft
cloud cover. However, due to downslope winds into the valley, high
resolution model and HREF show this moisture diminishing as it
moves into the valley. Wednesday looks dry with clear sky.
&&
.CLIMATE...
Daily Record Low Minimum Temperatures
Date Chattanooga Knoxville Tri-Cities Oak Ridge
10-31 25(1954) 28(1954) 24(1952) 24(1954)
11-01 27(1993) 23(1874) 26(1993) 28(1993)
11-02 22(1954) 22(1954) 24(1993) 22(1954)
&&
.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN 31 52 27 59 / 0 0 0 0
Knoxville McGhee Tyson Airport, TN 28 49 25 57 / 0 0 0 0
Oak Ridge, TN 26 49 25 56 / 0 0 0 0
Tri Cities Airport, TN 26 45 22 54 / 0 0 0 0
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...Freeze Warning until 10 AM EDT Wednesday for Cherokee-Clay.
TN...Freeze Warning until 10 AM EDT /9 AM CDT/ Wednesday for Anderson-
Bledsoe-Blount Smoky Mountains-Bradley-Campbell-Claiborne-
Cocke Smoky Mountains-East Polk-Grainger-Hamblen-Hamilton-
Hancock-Hawkins-Jefferson-Johnson-Knox-Loudon-Marion-McMinn-
Meigs-Morgan-North Sevier-Northwest Blount-Northwest Carter-
Northwest Cocke-Northwest Greene-Northwest Monroe-Rhea-
Roane-Scott TN-Sequatchie-Sevier Smoky Mountains-Southeast
Carter-Southeast Greene-Southeast Monroe-Sullivan-Unicoi-
Union-Washington TN-West Polk.
VA...Freeze Warning until 10 AM EDT Wednesday for Lee-Russell-Scott
VA-Washington VA-Wise.
&&
$$
SHORT TERM...DH
AVIATION...DH
Area Forecast Discussion
National Weather Service Phoenix AZ
455 PM MST Tue Oct 31 2023
.UPDATE...
00Z Aviation Discussion.
.SYNOPSIS...
Occasionally breezy conditions will continue across parts of
south-central Arizona through Wednesday. Meanwhile, high pressure
will predominate across the Desert Southwest the next several
days, resulting in a gradual warming trend and a return to above
normal temperatures by Thursday. Dry conditions are favored to
persist through at least early next week.
&&
.DISCUSSION...
Latest RAP analysis depicts dry northerly flow aloft across the
Desert Southwest, sandwiched between a ridge across the
intermountain West and a broad trough across much of the northern
CONUS. At the surface, a strong 1036 mb high across the northern
Plains is producing a pronounced easterly flow across Arizona.
Sustained winds of 15-20 mph have been observed across the Valley
this morning, while further east in the higher terrain, gusts
reached as high as 40 mph earlier this morning at Apache Lake.
Latest HREF indicates the gusts will subside, though sustained
winds of 10-15 mph will persist into this evening across the
Valley. Meanwhile, skies remain clear and near to slightly below
normal temperatures are anticipated this afternoon. Below normal
dewpoints in the teens and twenties will also persist.
Latest ECMWF EFI gust values drop off considerably tonight as the
aforementioned surface high migrates eastward, though latest HREF
still indicates a high likelihood of at least occasional
breeziness Wednesday morning across central Arizona. This will
keep temperatures a bit higher than they potentially could be.
However, sheltered areas such as along the lower Colorado River
Valley near Parker will drop into the 40s. Latest NBM indicates
there is even a 20-40 percent chance temperatures will drop into
the 30s in these areas early Wednesday morning.
Looking at the bigger picture, latest ECMWF ensembles show
positive height anomalies prevailing cross the Desert Southwest
through at least early next week. Initially, the ridge across the
intermountain West will migrate east and weaken. This will quickly
be replaced by another ridge along the West Coast. That system
will also weaken as it slides eastward, but as it does so another
zonally-oriented ridge in the eastern Pacific will build eastward
through the subtropics this weekend and into early next week. This
will translate into a gradual warming trend and a return to above
normal temperatures as soon as Wednesday or Thursday. Model
clusters are also exhibiting little variability and with PWATs
likely remaining below normal, the pattern will remain unfavorable
for any precipitation across the Desert Southwest.
&&
.AVIATION...Updated at 2350Z.
South-Central Arizona including KPHX, KIWA, KSDL, and KDVT:
VFR conditions are anticipated throughout the forecast period.
Easterly winds with occasional gusts up to 18-20 kts will be
possible through sunset. Otherwise, winds will maintain an east to
northeasterly component with speeds around 10 kts or less. Early
tomorrow, winds will increase again with gusts reaching 15-18 kts
at all terminals, but should gradually diminish through the
afternoon. Skies will remain mostly clear overnight before high
cirrus begins to overspread the region early tomorrow morning.
Southeast California/Southwest Arizona including KIPL and KBLH:
No aviation concerns will exist through the forecast period. North
to northwesterly winds below 10 kt will be favored at both TAF
sites, although KIPL will back to a more westerly component
overnight into the early tomorrow morning. SCT-BKN high cirrus
will enter the area as early as 04Z and will persist through the
end of the TAF period.
&&
.FIRE WEATHER...
Gusty easterly winds will exist again today across parts of south-
central Arizona with the strongest gusts favoring ridgetops east of
Phoenix. The strongest gusts may exceed 30 mph in some places.
Combined with Min RHs around 10-20% in these areas, elevated fire
weather conditions will exist today. Winds weaken Wednesday but dry
conditions will persist with Min RHs around 10-15% for most areas
through the remainder of the week. Temperatures will remain near
seasonal normals over the next couple of days as lower desert highs
top out in the low to mid 80s before gradually warming above normal
heading into the end of the week.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&
$$
DISCUSSION...Hirsch
AVIATION...Salerno
FIRE WEATHER...Smith