Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/06/21
Area Forecast Discussion...UPDATED
National Weather Service Albuquerque NM
619 PM MDT Tue Oct 5 2021
.AVIATION...
00Z TAF CYCLE
An upper low moving into western AZ will continue to draw moisture
north into western NM. Deteriorating conditions will continue at
KFMN- KGUP with rain impacts, a stray lightning strike, occasional
wind gust of 25kt to 30kt and possible patchy fog. This will all
lead to MVFR cigs and vsbys from around 06Z through 15Z Wednesday.
We can`t rule out brief IFR conditions in a heavier rain shower.
Showers will be much more isolated east of the Continental Divide
into the Rio Grande for KSAF, KABQ and KAEG, and there is not enough
confidence to put in a TEMPO group for a shower past midnight into
Wednesday morning. Overall conditions improve in the western half by
Wednesday afternoon with VFR conditions expected.
&&
.PREV DISCUSSION...254 PM MDT Tue Oct 5 2021...
.SYNOPSIS...
Showers and a few thunderstorms will increase across western New
Mexico through the overnight hours and may reach the Rio Grande
Valley after midnight, as a low pressure system approaches. Rain
chances remain across the northern portion of the state Wednesday
afternoon, as the system exits. Mild and drier conditions are
forecast for Thursday, then another storm system will bring
precipitation chances to the northern third of the state this
weekend. This system will also bring cooler temperatures and
increased winds.
&&
.DISCUSSION...
SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT)...
An potent upper low has moved ashore southern CA today, spinning up
anomalously high subtropical moisture into AZ. Strong diffluent flow
aloft coupled with steep instability has prompted a severe weather
threat for our neighbors to the west. The good news is this upper
low will open up as it moves into the Four Corners region overnight,
leaving isolated-scattered thunderstorms with bands of locally
moderate to heavy rainfall likely entering far western NM late this
evening. Shower coverage drops substantially east of the continental
divide thanks to the upper low continuing to open and weaken and
downslope flow. Abundant low level moisture will be left in this
system`s wake across western NM into the Rio Grande, evident by Td`s
staying in the upper 40s and modeled PWATs reaching ~0.80" at ABQ in
the 90th percentile climatologically speaking. Opted to maintain the
prior forecast`s mention of patchy fog along and west of the
continental divide early Wednesday morning as a result.
The eastern plains stay dry as skies clear out area wide mid-to-late
Wednesday morning. CAMs such as the HREF and HRRR are showing enough
remnant boundary layer moisture across western and central NM
becoming mixed out and producing scattered light shower activity
during the afternoon period. These should be fairly light in nature
and opted to only add in a mention of sprinkles for this forecast
package. With drier mid to upper level air and subsidence behind the
trough passage, showers should have a difficult time building to
anything substantial. Gusty winds will likely be the main impact.
LONG TERM...(THURSDAY THROUGH TUESDAY)...
A weak ridge builds over the state on Thursday, with a brief break
in between systems. Drier conditions are forecast, with a few
afternoon breezes thanks to the development of a leeside low. An
upper-level trough begins to drop into the Great Basin region on
Friday, increasing southwest flow aloft. Afternoon breezes continue
on Friday, as another leeside low develops across southeastern
Colorado. This system will also bring precipitation chances to far
northern New Mexico just near the Colorado border over the weekend.
The 12z GFS has the quicker timing of the trough, with it crossing
northern New Mexico late Saturday/early Sunday and a tighter gradient
than the ECMWF. A 50-55 kt 700 mb jet crosses the state on Saturday.
This could mean the strongest winds (according to the GFS) will be
late Saturday/early Sunday ahead of the passage of the cold front.
Although model guidance has trended wind speeds down since
yesterday, winds were still increased above NBM guidance for
Saturday. Temperatures drop back below normal across western and
central NM early next week, while the eastern plains stays a few
degrees above normal. Temperatures warm a few degrees on Monday,
before another strong closed low looks to impact the state Tuesday or
Wednesday next week. This system will feature much cooler
temperatures (GFS 700 mb temperatures around -5 C), more
precipitation chances across the north, a 60+ kt 700 mb jet that
crosses the state Tuesday afternoon, and NBM winds already near or
exceeding wind advisory criteria across the east.
24/31
&&
.FIRE WEATHER...
A potent upper low will bring substantial wetting rain chances to
the western third of the forecast area tonight into Wednesday
morning. Conditions clear Wednesday with a ridge of high pressure
building overhead for the middle of the week. Mostly calm weather
with good to excellent ventilation results. Southwest winds increase
Friday and into the weekend with two weather systems skirting
NW and northern NM Friday and Saturday respectively. Daytime high
temperatures reach 10-15F above normal through the eastern plains
with strong gusts of 25-35mph possible. Short-lived and patchy
critical fire weather is possible both days as a result. Cooler
weather settles in thereafter Sunday.
24
&&
.AVIATION...
18Z TAF CYCLE
An upper low is moving ashore the northern Baja this hour with
encroaching shra/tstms to the NM/AZ border by ~22Z. Deteriorating
conditions will ensue thereafter at KFMN-KGUP with mostly a -ra
impact. Instability is expected to decrease overnight as the upper
low opens. However, cannot entirely rule out a stray lightning strike
west of the divide. Patchy fog and reduced vis will be a concern as
well for these areas along and west of the divide. Showers will be
more scattered east of the divide into the Rio Grande from KSAF-KABQ
past midnight into early Wednesday morning, a stray gust may also
ensue. Overall conditions clear past Wednesday morning area wide.
24
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Area Forecast Discussion
National Weather Service El Paso TX/Santa Teresa NM
505 PM MDT Tue Oct 5 2021
.AVIATION...00Z TAF CYCLE...
West of Deming...SCT/BKN080 BKN250 isolated OVC040CB 5SM TSRA
spreading as far east as Akela-T or C. Conditions improving after
06Z to SCT100 SCT/BKN250. Wind gusts to 35KT near storms. East of
Akela-T or C...SCT/BKN080 BKN250 until 06Z...then FEW080 SCT250.
Variable winds less than 8KT. Winds Wednesday afternoon southwest
10-15KT.
&&
Hefner
.PREV DISCUSSION...324 PM MDT Tue Oct 5 2021...
.SYNOPSIS...
There a chance of light showers and brief thunderstorms for areas
west of Las Cruces this afternoon and evening. A few light showers
may also occur across the region on Wednesday. Afterwards, an
extended period of dry conditions and warm temperatures will occur
through this weekend and into next week. Southwesterly winds will
become increasingly breezy through Saturday with some areas
becoming windy. Another round of even stronger winds will be
possible next Tuesday as a weather system passes north of the
area.
&&
.DISCUSSION...
.SHORT TERM...Tonight and Wednesday...
Current mid-level water vapor imagery, overlayed with 500-mb RAP
Analysis shows a closed low moving onshore over the San
Diego/Tijuana vicinity. Out ahead of the center of circulation on
the western periphery, moisture and forcing in the mid-levels of the
atmosphere can be seen. Latest visible satellite imagery confirms
the presence of moisture and forcing for ascent across much of AZ
and western NM. As of 12PM, the radar remains relatively quiet
except for showers moving across areas west of the Divide, with most
of the activity over AZ. That will change as we progress through the
afternoon and evening hours. The upper-level low will move NE over
southern NV/NW AZ vicinity by this evening. As it treks eastward,
the moisture and forcing associated with the system will move over
western NM. Thus, showers and thunderstorms can be expected for
areas west of the Rio. Convective and instability parameters aren`t
the greatest, but some of the parameters will be there. With shear
around 30 kts, CAPE between 500-100 J/kg, and LI`s around -2, a
strong storm or two cannot be ruled out, with the greatest threat
being strong winds. Afternoon/evening forecast soundings show a
decent inverted-V sounding with Downdraft CAPE of ~1000 J/kg.
This evening, the closed low will weaken and open up into trough. In
response, forcing for ascent and instability parameters will weaken
over the central portion of the forecast area. Showers and storms
will likely dissipate before reaching the Rio Grande Valley, with
light showers remaining. Clouds will stick around during the
overnight hours as moisture from the system slowly moves east.
On Wednesday, a deep trough will move onshore over the PacNW. As it
does so, the system over the Great Basin will get absorbed into the
main steering flow aloft and quickly move towards the northeast. In
response, a shortwave ridge will nose in from the southwest as high
pressure gets established over Mexico. This will lead to a quiet
Wednesday as winds aloft become west/southwesterly. A shower or two
will be possible east of the Rio, where small amounts of moisture
remain.
&&
.LONG TERM...Wednesday Night through next Tuesday...
An extended period of dry conditions with warm temperatures is
expected through the first part of next week. A dry and steady
southwest flow will occur over the state with an area of high
pressure aloft sitting just south of the border. A series of open
troughs or waves will pass over the area Friday, Saturday and
Tuesday. Each system will be stronger than the one before it. All
of them are currently on a track that puts them north of area,
meaning rain chances will be close to zero during the period.
One weather impact that these systems will be producing for the
area is stronger winds. As part of the steady southwest flow there
will be day time mixing that will bring stronger winds aloft down
to the surface. The series of weather systems passing north of
the area will tighten the pressure gradient as they move into the
state and induce a surface trough in northeast New Mexico. This
combined with the winds aloft will help to increase winds in the
afternoon of Friday, Saturday and Tuesday. Wind speeds on Friday
will be generally lightly breezy from the west to southwest. Wind
speeds on Saturday afternoon will be breezy to windy as the
stronger weather system passes north of the area.
Long range models have the weather system on Tuesday becoming
much stronger but still passing north of the area in the Four
Corners Region. This system will significantly tighten the
pressure gradient and allow much stronger winds to mix down to the
surface setting up a potential for strong windy day and possible
blowing dust. Later model runs may weaken this system over time,
so it is too early to consider advisory or warning thresholds, but
next Tuesday could have significant winds.
Day time temperatures in the extended period will be on a mild
rollercoaster of sorts as warmer several degree above normal
temperatures occur Thursday through Saturday. There will be a
cool down back to near seasonal normals Sunday and Monday with a
warm up ahead the system next Tuesday with an expected cool down
to follow it the rest of next week.
&&
.FIRE WEATHER...
No significant fire concerns for the next few days. An upper-level
low will approach the area this afternoon and evening, bringing an
increase in moisture, along with an increase in rain and storm
chances. Greatest chances for rain will be for areas west of the Rio
Grande Valley. Min RH values will range to near 40 toward the AZ
border, with areas near 20 along and east of the Rio. Rain chances
will end overnight, giving way to a dry Wednesday. The return of dry
air will bring another day with Min RH values in the mid 20s. Winds
will top out around 15 MPH each afternoon. A drying trend will
finish out the week with breezy conditions expected for Saturday and
Sunday. This could lead to near critical conditions, though RH
values should stay above 15 percent. The vent rate for the next few
days will range from good to very good.
&&
&&
.PRELIMINARY POINT TEMPS/POPS...
El Paso 63 87 63 89 / 10 0 0 0
Sierra Blanca 56 80 56 82 / 0 0 0 0
Las Cruces 57 84 55 85 / 10 0 0 0
Alamogordo 58 83 57 85 / 10 10 0 0
Cloudcroft 43 61 42 63 / 20 20 0 0
Truth or Consequences 58 82 55 83 / 10 0 0 0
Silver City 52 73 52 74 / 30 0 0 0
Deming 56 84 54 85 / 30 0 0 0
Lordsburg 55 81 55 82 / 40 0 0 0
West El Paso Metro 65 87 64 88 / 20 0 0 0
Dell City 56 85 57 87 / 0 0 0 0
Fort Hancock 60 88 60 91 / 0 0 0 0
Loma Linda 58 78 58 81 / 0 0 0 0
Fabens 61 87 62 89 / 10 0 0 0
Santa Teresa 59 84 58 86 / 20 0 0 0
White Sands HQ 61 84 61 86 / 10 10 0 0
Jornada Range 59 82 58 84 / 10 0 0 0
Hatch 58 83 55 84 / 10 0 0 0
Columbus 59 84 58 85 / 30 0 0 0
Orogrande 59 83 58 86 / 10 10 0 0
Mayhill 48 71 48 74 / 10 20 0 0
Mescalero 47 72 46 73 / 20 20 0 0
Timberon 47 70 46 71 / 10 20 0 0
Winston 45 74 43 76 / 20 0 0 0
Hillsboro 55 80 54 81 / 20 0 0 0
Spaceport 57 81 55 82 / 10 0 0 0
Lake Roberts 46 73 45 74 / 30 0 0 0
Hurley 50 77 50 79 / 30 0 0 0
Cliff 48 81 47 81 / 50 0 0 0
Mule Creek 50 75 50 76 / 50 0 0 0
Faywood 54 77 52 78 / 30 0 0 0
Animas 54 83 54 84 / 50 0 0 0
Hachita 54 82 54 83 / 40 0 0 0
Antelope Wells 54 83 55 84 / 40 0 0 0
Cloverdale 54 78 53 78 / 60 0 0 0
&&
.EPZ WATCHES/WARNINGS/ADVISORIES...
NM...None.
TX...None.
&&
$$
Area Forecast Discussion
National Weather Service Grand Forks ND
1104 PM CDT Tue Oct 5 2021
.UPDATE...
Issued at 959 PM CDT Tue Oct 5 2021
Near critical fire weather conditions have since improved, however
there will still be breezy winds out of the south around 10-15 mph,
with sporadic higher gusts.
These increased winds will help mix warmer temps aloft. Used the
HRRR for guidance on localized areas of warmer overnight temps
from terrain interaction with a nocturnal low level jet that will
set up eastern ND into southern MB tonight.
UPDATE Issued at 636 PM CDT Tue Oct 5 2021
Focus in the near term has been on fire weather conditions.
Satellite has indicated multiple fire signatures throughout the
FA, most of which are likely agricultural presenting minimal
impact. However, there are still a couple within northwest
Minnesota that are likely wildfires. One in northeastern Kittson
County with clear thermal and visible signature, and another very
near Itasca State Park. The thermal signature within Polk County
this afternoon was from a prescribed burn.
Weather conditions wrt to fire potential should be improving as
daytime heating ceases allowing RH values to begin their climb
above 30%. While gusty winds within eastern ND and into the
northern Red River Valley are starting to lessen, a breeze out of
the south will remain in place tonight with winds steady around 15
mph.
Tomorrow may be a similar day as today in terms of fire weather
potential.
&&
.SHORT TERM...(This evening through Wednesday night)
Issued at 224 PM CDT Tue Oct 5 2021
Impactful weather is not expected today into Wednesday. Look for
mostly clear skies with temperatures pushing into the middle 70s to
near 80 degrees. A rather amplified H5 ridge is responsible for the
recent warmth as it moves slowly across the northern CONUS.
Southerly winds are expected to continue through Wednesday and into
Thursday, with gusts to near 25 mph developing once more Wednesday
afternoon.
Low RH values are forecast once more for Wednesday, however,
slightly higher dew points will keep the minimum RH in the 25 to 30
percent range.
.LONG TERM...(Thursday through Tuesday)
Issued at 224 PM CDT Tue Oct 5 2021
The long term period continues to show low impacts through the late
week, with rain and/or thunderstorm potential from Friday through
the upcoming weekend. Ridging over the central US, with zonal flow
across Canada, will keep the region dry through Thursday, before the
central CONUS ridge translates east enough to get the northern tier
tapped into the SW flow aloft now over the PAC NW. A shortwave
trough is progged to move across North Dakota late Thursday with a
stronger wave on Saturday, giving a period of unsettled weather from
Friday through Sunday. Deterministic H500 models show improved
consistency on timing the upper level waves, while GEFS plumes
continue to show a decent signal for increased moisture after 09/12Z
(Saturday morning). Continue to have fairly high confidence given
the aforementioned GEFS plumes across the region. Bigger question
will be potential for thunder given shorter, fall days, but for
continuity purposes will keep the ongoing isolated TS.
Thursday will see highs in the 70s and 80s before falling into the
60s and 70s for the weekend. he cooler air will stay in place for a
cool and dry start to next week.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 1104 PM CDT Tue Oct 5 2021
VFR conditions are expected throughout the TAF period for all
sites. However, elevated winds out of the south will remain in
place, staying steady around 15 kt tonight. LLWS is expected
tonight between 01-10 UTC for KDVL, KGFK, and KTVF. Winds
increase again Wednesday between 14-00 UTC with gusts to 30 kt possible.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...None.
MN...None.
$$
UPDATE...CJ
SHORT TERM...Lynch
LONG TERM...Speicher
AVIATION...CJ
Area Forecast Discussion
National Weather Service Goodland KS
945 PM MDT Tue Oct 5 2021
.UPDATE...
Issued at 942 PM MDT Tue Oct 5 2021
Based on local research, the pattern is looking favorable for the
potential of blowing dust to develop Tuesday afternoon, mainly
along and west of the Kansas-Colorado border. Blowing dust would
potentially come into the area from the southwest. Confidence is
low at this time of blowing dust occurring since this is seven
days away. October is a prime month for blowing dust events in the
Goodland area of responsibility. Stay tuned for further updates.
&&
.SHORT TERM...(This evening through Thursday Morning)
Issued at 116 PM MDT Tue Oct 5 2021
RAP analysis shows the Tri-State area in high pressure with a broad
low over the Mississippi Valley and a trough approaching the Four
Corners region. Clear skies will exist thanks to the high pressure
for the rest of the day and through the night as afternoon highs
will be in the 80s. Elevated to near critical fire weather concerns
remain mainly west of Highway 27 through the remainder of the
afternoon as RH values fall into the lower 20s to upper teens this
afternoon; any near critical area look to remain across east
Colorado where winds are slightly breezier and RH`s are lower.
Tonight, low level moisture will slowly increase from the eastern
low as winds remain out of the SSE around 10 knots or less. For this
package overnight lows were raised slightly to account for the
moisture advection as this should limit how much overnight
temperatures fall due to radiational cooling via the lack of cloud
cover. Widespread lows in the 40s are expected but wouldn`t be
surprised if a few locales in lower lying regions fall into the
upper 30s.
Wednesday, the low from the east drifts slowly to the west as the
trough over the western CONUS moves NE towards the Rockies. These
two synoptic features look to collide roughly over western Kansas
where a tight pressure gradient develops. Forecast soundings
indicate near 30 knots of wind through out the mixing level, which
should have no problem transporting to the surface due to the clear
skies. Winds will be noticeably breezy as sustained winds of 15
knots with gusts up to 30 knots likely. Elevated to near critical
fire weather again looks possible albeit the more moist airmass,
even though RH values over east Colorado fall into the lower 20s.
Another feature to keep an eye on is the trough from the west as a
weak shortwave is associated, as it sparks some showers over the
Front Range Wednesday afternoon. A slight eastward shift with the
overall trough may create enough lift for a stray shower or two
across east Colorado during the late afternoon/ early evening
hours due to the shortwave as the increase in overall moisture in
conjunction may create enough lift. Confidence in this scenario
is low and not high enough to introduce showers into the forecast
at this time. Highs for Wednesday look to be in the upper 70s to
low 80s and overnight lows in the mid 40s to low 50s as some
clouds move in from the west.
.LONG TERM...(Thursday through Tuesday)
Issued at 110 PM MDT Tue Oct 5 2021
Westerly flow aloft.. on the northern periphery of a broad upper
level ridge situated over the Central/Southern Plains.. will back
to the SW late this week (Fri-Sat) as a broad upper trough
progresses ashore the Pacific Coast. The aforementioned trough is
anticipated to progress east across the central CONUS during the
weekend. By late weekend.. guidance suggests that robust shortwave
energy will dig SE-SSE ashore the PAC NW.. amplifying into a
robust upper low invof the 4-Corners early next week.
Above normal temperatures and dry conditions are likely to
persist through Friday (perhaps into Saturday). With an
increasingly unsettled synoptic pattern, expect cooler
temperatures and increased cloud cover late this weekend -- along
with above average chances for precipitation early next week.
At this range.. confidence is very low with regard to
precipitation chances/amounts.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 942 PM MDT Tue Oct 5 2021
VFR conditions are expected through the TAF period at KGLD and
KMCK. Southeasterly winds generally under 10kts overnight will
increase to around 12-16kts gusting to 24kts by mid-day. After
sunset, winds will ease back to 9-13kts from the southeast.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...AW
SHORT TERM...TT
LONG TERM...VINCENT
AVIATION...AW
Area Forecast Discussion
National Weather Service Green Bay WI
1049 PM CDT Tue Oct 5 2021
Updated aviation portion for 06Z TAF issuance
.SHORT TERM...Tonight and Wednesday
Issued at 249 PM CDT Tue Oct 5 2021
High pressure over the region will preclude any risk of
precipitation over then next 24 hours. The main forecast issue to
be on the extent of fog tonight with locally dense fog possible.
The 19Z MSAS surface analysis showed this high pressure situated
over northern sections of the Great Lakes. Anticyclonic flow
around this high had brought an east-northeast wind into the
forecast area with lake moisture and daytime heating aiding in low
clouds over all but far northeast WI.
The high pressure and an upper-level ridge to remain parked over
the Great Lakes region tonight, bringing light winds and an
easterly fetch off of Lake MI. Time sections show plenty of low-
level moisture across WI, thus the favorable scenario of more low
clouds and fog can be expected mainly during the overnight hours.
Based on the positioning of the high pressure, anticipate northern
WI to have thicker fog compared to central/east-central WI. This
would include dense fog and the eventual need of an advisory.
Prefer to let next shift see the fog develops this evening, thus
no headlines right now. Min temperatures to range from the middle
40s to around 50 degrees north, lower to middle 50s south.
The fog is expected to linger through mid-morning Wednesday before
slowly lifting into a stratocu deck. The high pressure and upper
ridge both slowly shift east during the day, but the light wind
field may take mixing a while to shake these low clouds. Look for
skies to eventually become partly to mostly sunny with max
temperatures in the middle to upper 60s near Lake MI, upper 60s to
lower 70s inland.
.LONG TERM...Wednesday Night Through Tuesday
Issued at 249 PM CDT Tue Oct 5 2021
Focus in this part of the forecast mainly revolves around precip
chances in the Thursday-Friday and Sunday-Monday time frames. Models
have strength/timing differences regarding the system for Sunday and
Monday, but are in reasonable agreement into early this weekend.
Wednesday night through Thursday night...Upper level low pressure
will be shifting north across the mid-Mississippi Valley on
Wednesday night. Will see increasing clouds through the night. But
high pressure will remain across the Great Lakes though and dry air
should slow the northward push of light showers. Will keep the
forecast dry. The upper low makes slow northward progress on
Thursday and Thursday night. Scattered showers seem like a decent
bet to slide in from the south at times. A few thunderstorms cannot
be ruled out since instability of 200-400 j/kg shifts into central
to northeast WI. But instability this low is too low for severe
weather chances given the poor dynamics. Mild temperatures over
this period.
Rest of the forecast...The upper low/trough will lift northeast
across the region on Friday, and showers and spotty storms will
continue until the trough exits on Friday night. Broad southwest
flow will remain aloft on Saturday as low pressure organizes over
the central plains. Some clouds and/or fog may linger over far
northern WI on Saturday morning, but then should see clearing
through the day. Saturday looks like the warmest day over the next
7 days with highs in the low to mid 70s. By Saturday night into
Sunday, low pressure will be lifting northeast across the northern
Plains while a cold front moves east across Wisconsin on Sunday. A
ribbon of instability could arrive ahead of the front on Sunday, but
timing of the front will help determine how widespread thunderstorm
potential will be. Some rap around showers could linger into Monday
behind the system.
&&
.AVIATION...for 06Z TAF Issuance
Issued at 1049 PM CDT Tue Oct 5 2021
Conditions were mainly VFR across the region this evening, with
some remaining cloud cover across portions of central and east-
central Wisconsin and an area of stratus coming onshore across
Door County. High pressure overhead along with light winds and
sufficient low-level moisture is forecast to allow for fog to
develop once again during the overnight hours. There are already
signs of fog forming across portions of north-central and central
Wisconsin at issuance. This fog may again become locally dense,
especially at the RHI TAF site which would persist into early
Wednesday morning. Much like today, it may take some time for the
fog to dissipate and low clouds to mix out, thus lingering MVFR
cigs may persist through most of the morning hours before lifting
to VFR cigs in the afternoon and continuing into Wednesday
evening.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....AK
LONG TERM......MPC
AVIATION.......Kurimski
Area Forecast Discussion
National Weather Service Elko NV
323 PM PDT Tue Oct 5 2021
.SYNOPSIS...Weather conditions trend cooler and wetter as a more
active pattern sets up aloft. Active weather is likely to continue
through the rest of the week before we see a potential break in
the pattern over the weekend.
&&
.SHORT TERM...Tonight through Thursday
A weak disturbance continues to lift through Utah this evening with
some wrap around moisture allowing for a couple of light showers
to linger near the NV/UT border. Showers that occurred earlier
today to our south were producing a little bit of thunder, but
instability doesnt look sufficient for much in the way of
thunder tonight, but we wont rule it out.
Showers begin to form in parts of central and east-central Nevada
sometime during the late morning and early afternoon on
Wednesday. The main band of precipitation is expected to cover a
large swath oriented southwest to northeast through central and
northeastern Nevada. Essentially, the main precipitation looks to
run from the Austin/Eureka/Grass Valley area through the Mountain
City/Jarbidge/Jackpot area. QPF totals should be around the 0.2
to 0.3 inches for Wednesday where the most persistent rainfall
occurs. Light showers can be expected outside of the swath
mentioned here, but totals are much lower with less than 0.10
likely. Snow levels stay in the mountaintops.
Showers taper off for most into the overnight hours, with the
exception being Elko county. Thursday sees a similar situation,
except the main swath of showers looks to stay confined to Elko
county initially, before there is a shift to a boundary from
Lander county through northeastern Elko county. Rainfall totals in
this stretch are currently expected to be around 0.10 to
0.15, but once again light showers are very much possible
outside of this swath. Snow levels still look to stay in the
mountaintops.
The takeaway is that some much needed precipitation is on its way,
but this pattern is bringing cooler air also. Look for 60s and 70s
for Wednesday and mainly 60s on Thursday. Overnight lows dip into
the 30s.
.LONG TERM...Thursday night through next Tuesday.
The transition to winter has begun with an active weather pattern
through the period, although there will be a break Saturday night
and Sunday. Ensemble solutions show decent agreement, particularly
on Day 7 (next Tuesday) with such a deep cold trough over the
entire inter-mountain West. Not necessarily in absolute terms, but
expect more spread between model solutions given the significant
pattern change. Bottom line, its turning colder and wet and
snow levels could lower to the valley floors with significant
mountain snow.
The first dynamic wave is not as cold as a offshore California
wave lifts toward Utah on Friday, crossing central/southern Nevada
in the process. This is a moist wave and showers will be
developing Thursday night and widespread on Friday. Because this
system originates from the southern stream, snow levels will be
high and around 9K feet, although it could fluctuate a bit. Below
mountain peaks and ridges, precipitation type will be rain. The
potential exists that this will be a decent soaking rain with
valley amounts possibly a quarter inch or so, upwards to a half
inch across northern Nevada north of I80.
After a break on Saturday night and Sunday, the next upstream
trough makes its presence known. A deep closed low circulation
digs southeast somewhere over California or Nevada Monday
afternoon through Tuesday time frame. Strong dynamics and mid
level cold advection will may result in widespread rain or snow
with the snow levels lowering into the valley floors. There is
uncertainty with respect to temperatures and QPF, meaning a little
snow falls in the valley or the snow becomes impactful with
significant snow over mountain passes.
&&
.AVIATION...Look for VFR conditions through the next 24 hours.
A ribbon of smoke/haze may impact KWMC and visibility lower to
6SM this evening. The smoke plume is currently west of KWMC, but
this plume is expected shift east and over KWMC after 03Z this
evening. Due to changing transport winds, this narrow plume will
shift farther east and the visibility at KWMC should improve.
At KELY, showers will be in the vicinity although current HRRR
projections keep showers over the higher terrain. Showers will be
spotty surrounding KELY, but a 1 in 5 chance that a showers moves
overhead.
VFR prevails at KBAM, KEKO, and KTPH. Local gusts 20-25KT range
is possible Wednesday afternoon.
&&
.FIRE WEATHER...Some instability exists these next few days, so we
aren`t ruling out any thunderstorms across the region. However,
with the moisture this system is bringing in, these thunderstorms
are expected to be wet. Any thunderstorms should also be isolated
in coverage.
&&
.LKN WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
84/88/88/84
AREA FORECAST DISCUSSION
National Weather Service Morristown TN
918 PM EDT Tue Oct 5 2021
.UPDATE...
EVENING UPDATE.
&&
.DISCUSSION...
Increase in light returns on the radar during the last hour, but
so far not much more than sprinkles in the northern/central valley
downslope areas. Will adjust PoPs a bit to show these trends, but
will also remove thunder for the first few hours of the night all
areas and for the entire night in the northern/central valley.
Will tweak temps and dew points as well with this update. Will
leave the Flash Flood Watch as is for now with the start time of
12Z.
&&
.AVIATION...
00Z TAF DISCUSSION.
Will see showers and possibly a few thunderstorms increase again
later tonight into Wednesday, with CHA having the best chance for
MVFR or lower conditions as well as thunder. TYS/TRI will be
influenced by downslope flow as the low level flow will be
southeast over the mountains, so expect primarily VFR conditions
both sites. However, there may be some brief lower conditions
mainly with any showers/thunderstorms.
LW
&&
.PREV DISCUSSION...
/ISSUED 331 PM EDT Tue Oct 5 2021/
SHORT TERM...(Tonight and Wednesday)...
Key Points:
1. We remain warm and moist with scattered showers and
thunderstorms producing locally heavy rainfall rates.
2. Any training convection will result in flash flood potential
across the southern plateau, southern valley, and southwest North
Carolina.
Discussion:
A stacked low pressure system across the Lower
Mississippi Valley will slowly meander northward on Wednesday with
deep southerly unidirectional flow across the forecast area. This
will result in an anomalously moist airmass across the forecast
area, especially across the southern third of the forecast area
where downslope S/SE flow will not result in any localized drying
of the boundary layer. In fact, upslope flow along the southern
plateau into the Chattanooga area will likely enhance low-level
convergence and convective initiation late Wednesday into
Wednesday night and enhance rainfall totals for these locations.
The environment is favorable for heavy rainfall. RAP and HREF
guidance show PWAT values near 1.7 to 1.8 inch across the southern
plateau and southern valley late Wednesday into Wednesday night
with saturated forecast soundings showing a deep warm cloud layer
of 12-13k ft. With the RAP indicating weak, skinny instability
with MLCAPE around 500 J/kg across our southern zones, this will
result in an environment favorable to heavy rain rates within
developing convection. USGS stream gauges show streamflows already
near the 90th percentile, so antecedent wet soil will favor quick
runoff and enhance flooding risk from any heavy rain rates. At
this time, the severe weather risk remains very low with SPC
keeping the marginal risk to our southwest.
The highest risk for training convection will be Wednesday
afternoon and evening. At this time, the upper jet will move
northeastward with our area within the diffluent exit region. This
is the period of time where upper divergence will be at its
strongest and convective initiation will be most likely with SE
flow and low-level convergence along the southern plateau and into
the Chattanooga area. This can be seen in some of the recent 12z
CAM guidance such as the HRRR and hi-res 3km NAM which shows
convection developing Wednesday afternoon and slowly moving NNW
with training occurring as additional convection continues to
develop along the convergent boundary within a favorable
environment. Overall, this is a conditional threat. It depends on
the convection developing and training in this area which may
result in highly variable spatial distributions of rainfall
totals. However, the environment is favorable for flash flooding,
and with several CAMs showing very heavy rain rates on Wednesday
afternoon near our southern plateau and southern valley counties,
have issued a Flash Flood Watch for those locations.
JB
LONG TERM...(Wednesday night through Tuesday)...
Key Messages:
1. A wet pattern continues Wednesday night through Thursday with
drier conditions this weekend into next week.
2. Localized flooding a concern through Thursday morning across the
southern Plateau, southeast Tennessee, and southwestern North
Carolina.
3. Temperatures near to above normal through entire period.
Discussion:
Wednesday night through Friday night
Starting Wednesday night the mid/upper closed low over the lower
Mississippi River Valley will begin to lift northward overnight with
a southerly/southwesterly flow bringing moisture north from the Gulf
of Mexico. High precipitable water values and high streamflows
across the southern part of the forecast area will keep the chance
of flooding elevated through at least Thursday morning so Flash
Flood Watch continues for that area. With southeast low level flow
across northeast Tennessee rainfall amounts there will be light. As
the upper low moves into IL and then western Great Lakes by Thursday
night into Friday the bands of showers an occasional thunderstorms
will be less frequent and shift farther northeast into central east
Tennessee and northeast Tennessee. The Flood Watch in the southeast
part of the area may have to be extended depending on the movement
of the upper low. FFG values will likely be lower as well Wednesday
night into Thursday based on rainfall amounts during the next 24
hours. Temperatures Thursday and Friday will be similar to the past
few days in the lower to mid 70s.
Saturday through Tuesday
Starting Saturday a building ridge over the south central states
will begin to influence the region with height rises and drying of
the atmosphere. However a southerly flow mainly to the east of the
Appalachians will still affect the northeast corner with clouds and
a chance of showers. Saturday night and Sunday higher pressure will
be over the entire region and skies will become mostly clear even in
the northeast. A new fast moving trough and shortwave will push the
ridge and surface high eastward Monday and so another slight chance
of showers late Monday into Tuesday. This weak system looks like it
will begin to weaken or dissipate as it moves into the eastern
Tennessee Valley Tuesday. Temperatures Saturday through Tuesday will
be above normal in the mid 70s to lower 80s.
TD
&&
.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN 66 75 66 76 64 / 90 90 90 70 40
Knoxville McGhee Tyson Airport, TN 65 77 65 77 64 / 80 90 80 80 60
Oak Ridge, TN 65 76 64 76 63 / 80 90 80 80 70
Tri Cities Airport, TN 63 76 62 76 60 / 50 60 70 70 70
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...Flash Flood Watch from 8 AM EDT Wednesday through Thursday
morning for Cherokee-Clay.
TN...Flash Flood Watch from 8 AM EDT /7 AM CDT/ Wednesday through
Thursday morning for Bledsoe-Bradley-East Polk-Hamilton-
Marion-McMinn-Meigs-Northwest Monroe-Rhea-Sequatchie-
Southeast Monroe-West Polk.
VA...NONE.
&&
$$
Area Forecast Discussion
National Weather Service Nashville TN
944 PM CDT Tue Oct 5 2021
.UPDATE...
FOR EVENING DISCUSSION.
&&
.DISCUSSION...
Radar imagery this evening shows numerous showers and a few
thunderstorms across our southwest counties. This activity is
occurring along an axis of moisture convergence on the east side
of an upper level low centered south of Memphis. As the upper low
begins shifting northward overnight and Wednesday, several waves
of showers and thunderstorms will spread northward across Middle
Tennessee through the night and most of tomorrow, while gradually
shifting eastward with time. Focused moisture convergence could
lead to additional heavy rainfall and localized flooding in some
areas tonight and tomorrow, similar to what we`ve seen tonight
across Lawrence County. In addition, low level shear is forecast
to increase to around 20 knots on Wednesday afternoon/evening
with MLCAPE also rising into the 1000-1500 J/Kg range. This
indicates more rotating cells will be possible tomorrow, similar
to what the latest HRRR updraft helicity shows. Have updated all
grids/zones based on latest obs and model guidance, with high
likely/categorical pops for most of the area tonight and
Wednesday.
&&
.AVIATION...
00Z TAF DISCUSSION.
Isolated showers and storms could impact TAF sites off and on
throughout the overnight hours. Expect reduced visibilities and
cigs due to both rain and fog early Wednesday morning. Small
improvements in flying conditions are expected after 13z, through
MVFR cigs may linger into the afternoon hours. Winds will be
around 5 to 10 knots generally out of the east, unless a storm
moves directly over a terminal, in which case some gusty winds
will be possible.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
DISCUSSION......Shamburger
AVIATION........11
Area Forecast Discussion
National Weather Service Paducah KY
852 PM CDT Tue Oct 5 2021
.UPDATE...
Issued at 852 PM CDT Tue Oct 5 2021
Reworked PoP grids through 06Z based on the latest HRRR data and
then blended overnight to the existing forecast. The primary swath
of showers and storms through 06Z will work westward across
southern portions of southeast Missouri, while the band of showers
over southern Illinois weakens/dissipates as it moves west.
Thunder will likely be limited to southeast Missouri this evening,
but with the upper low approaching not willing to remove a mention
of thunder from any portion of the area at this time. Not confident
in the overnight trends. PoPs may be too high. Will re-evaluate
in a few hours.
UPDATE Issued at 657 PM CDT Tue Oct 5 2021
Updated aviation discussion for 00Z TAFs.
&&
.SHORT TERM...(Tonight through Thursday night)
Issued at 242 PM CDT Tue Oct 5 2021
Showers and thunderstorms continue to increase across TN early this
afternoon. Upper level energy will rotate NNW around the low and
supply the lift necessary for the showers and storms to continue and
spread NW across the area through the evening and overnight. Given
the close proximity of the low, the chance will continue through
Wednesday, though there may be a late night early morning lull
working northward in the wake of the initial batch of energy.
By Wednesday evening, the upper low should be over southern MO, with
the feature opening up and moving NNE to northern IL by 12z Friday.
It will not rain the entire time this feature is present. But, on
and off shower and thunderstorm chances will persist. There may be
zones of locally heavy rain throughout the event. But at this time,
not too concerned. Generally stayed close to the NBM for
temperatures.
.LONG TERM...(Friday through Tuesday)
Issued at 242 PM CDT Tue Oct 5 2021
The western semi-circle of the vertically stacked, southeast to
northwest oriented low should be oriented along the west Kentucky
Pennyrile and southwest Indiana during the morning/early afternoon
on Friday. Given the forcing and departing deep layer moisture, have
kept a small chance for showers in this area during the day on
Friday.
Beyond Friday,a broad vertically stacked ridge will build into the
WFO PAH forecast area Saturday into early Sunday. In coordination
and collaboration with surrounding NWS offices and utilizing
recommendations from the earlier midnight forecast shift, adjusted
high temperatures at or above the majority of the model guidance,
even the NBM initialization. Although the local forecast area should
remain sufficiently below record temperatures for Saturday,
widespread temperatures in the middle (and possibly upper 80s) are
forecast.
The next chance of measurable rain is expected to move near the WFO
PAH forecast late Sunday night into Monday. Although the current
(12z Tuesday)deterministic guidance from the European (ECMWF),
Canadian (CMCnh) and GFS suggest a good solid frontal passage during
the morning/midday hours on Monday (Canadian is about 3-6 hours
slower), the ensemble counterparts of the ECMWF/CMC are suggestive
of a lower/PoP QPF event at this time. The NBM initialization also
leaned toward a lower PoP event on Monday. If the signal for higher
PoPs/QPF remain strong and consistent with the deterministic
guidance, will considering raising PoPs/QPF for next Monday. At this
point in time, will stick with the NBM initialization. Given the
parallel nature of the wind fields and the orientation and depth of
the colder air, there is some indication that the better chances of
rain will remain behind the front, associated with the next
vertically stacked closed low. This should reduce any significant
surface based convection, markedly limiting severe potential. If
there is any convection that develops ahead of the front, it may be
weakly unstable, given the expected time of day for development.
With respect to temperatures and dewpoints, went slightly higher (1
degree) than the original NBM initialization and one degree lower in
dewpoints. No changes made to winds or general sky cover.
&&
.AVIATION...
Issued at 657 PM CDT Tue Oct 5 2021
Bands of showers and isolated thunderstorms will stream to the
northwest around an upper level low drifting slowly northward
across eastern Arkansas tonight into early Wednesday morning.
Expect a gradual reduction from VFR to MVFR ceilings during this
time frame along with periodic MVFR visibility reductions. A
relative lull in the precipitation is expected Wednesday morning
before the development of scattered showers Wednesday afternoon,
when ceilings should lift back to low end VFR. Light northeast
winds tonight will become southeast 5 to 10 knots on Wednesday.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
UPDATE...DRS
AVIATION...RJP
For frequently asked questions about the Area Forecast Discussion
visit...
http://weather.gov/saltlakecity/general/afd_faqs.php
Area Forecast Discussion
National Weather Service Las Vegas NV
818 PM PDT Tue Oct 5 2021
.SYNOPSIS...Isolated showers will remain possible over northeast
Clark and eastern Lincoln County tonight. Drier conditions return
Wednesday but active weather will continue as another storm system
arrives by late in the week with showers and gusty winds, especially
in the Sierra and southern Great Basin.
&&
.UPDATE...Severe thunderstorm threat for our area ended several
hours ago and the portion of Severe Thunderstorm Watch for Mohave
County was cancelled. Radar pretty quite right now with only some
isolated showers detected over northeast Clark and eastern Lincoln
Counties.
Upper low that produced the earlier fireworks is over southern
Mohave County and progged to continue moving east toward the Four
Corner overnight. HRRR shows a slight chance for a shower overnight
for northeast Clark and eastern Lincoln County. Elsewhere it will be
dry with some high clouds advancing inland ahead of our next weather
maker starting to take shape over the eastern Pacific. Update coming
out soon for tonight which was to trim back on PoPs. No changes
beyond tonight.
&&
.SHORT TERM...through Wednesday.
Very active convective pattern in place through this afternoon as
a closed low near San Diego lifts into the Desert Southwest and
interacts with anomalous moisture and marginal instability in
place. The Storm Prediction Center has issued a Severe
Thunderstorm Watch for Mohave County through this evening, which
is the first time Mohave County has been under a watch box since
September 23rd 2019. A line of storms earlier this morning brought
wind gusts to 68 mph to Kingman Airport and this line continues
to march northward east of Lake Mead as of the noon hour. Breaks
in the cloud cover and cooling mid level temps with the approach
of the closed low suggest additional development will remain
possible through this evening, particularly in Northwest Arizona
and far southern Nevada. The Las Vegas Valley has thus far
remained fairly dry, but scattered storms will remain possible
through the early evening.
Drier conditions resume Wednesday as the low shifts east, however
southwesterly flow aloft will result in increasing mid and high
clouds by late in the day spreading in from the west. Temperatures
in the afternoon will be pleasant and top out a few degrees below
typical early October normals.
.LONG TERM...Thursday through Tuesday.
Progressive, more fall-like pattern illustrated by ensemble guidance
will take us into next week. Next upstream trough coming out of the
Gulf of Alaska progged to split with southern stream energy digging
down the California Coast Thursday before turning inland across
southern California/Mojave Desert Friday. Expect increasing winds
along with another round of light showers. This system is colder and
may bring the first snowflakes to the higher elevations of the
southern Sierra. Additional energy coming down backside of trough
will keep it cool into Saturday with light showers possible over the
higher terrain. Even deeper trough possible early next week. Jury
still out on just how far south this trough may dig and just how wet
it might be. Right now, system looks to take a more inland
trajectory which would lead to a drier system. More confident that
it will become breezy and colder by the middle of next week.
&&
.AVIATION...For McCarran...Isolated showers and thunderstorms
possible through the afternoon, with the best chances between 20 and
00Z for the Las Vegas Valley. Associated with these storms will be
gusty outflow winds from the direction of the storms with gusts to
25 kts possible. Around sunset, storm chances will fall down, and
winds will become light and diurnal. SCT-BKN aoa 10-12 kft expected
through the overnight and morning hours.
For the rest of southern Nevada, northwest Arizona, and southeast
California...The bulk of showers and thunderstorms will continue
across northwest Arizona and southeast Nevada through 00Z before
becoming more isolated in nature around sunset with associated gusts
to 25 kts possible. After sunset, storm chances will fall off, and
winds will become light and diurnal. SCT-BKN aoa 10-12 kft expected
through the overnight and morning hours. KBIH may experience reduced
visibilities due to smoke after sunset, but not expected to drop to
MVFR conditions.
&&
.SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report
any significant weather or impacts according to standard operating
procedures.
&&
$$
UPDATE...Pierce
SHORT TERM...Outler
LONG TERM...Pierce
AVIATION...Varian
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