Forecast Discussions mentioning any of "ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 06/18/22

Area Forecast Discussion

National Weather Service Louisville KY

 950 PM EDT Fri Jun 17 2022

.Forecast Update...
Issued at 950 PM EDT Fri Jun 17 2022

Sure enough, a few blips have shown up on radar over SE Washington
county over the past several scans. The HRRR continues to show a few
showers drifting SE over the Louisville metro toward Midnight. Given
how consistent the HRRR has been with timing and placement, and we
are actually see some returns now on radar went ahead and added a 20
pop around the Louisville metro for a couple of hours.

Previous Update...
Issued at 855 PM EDT Fri Jun 17 2022

Things are quiet across the CWA at this hour, and it is largely
expected to stay that way overnight. However, we may still have an
outside shot an a few showers around the Louisville metro later this
evening. The cold front is showing up very nicely on mosaic radar
imagery dropping south of IND at this hour. It is actually moving at
a pretty good clip (around 20 mph) with a very notable and welcome
airmass change behind it (dew points in the 40s). As the front
approaches the Ohio River toward Midnight, it may set off an area of
agitated cu around the metro area. The HRRR has been consistently
showing a few showers later this evening with each run, so tough to
rule it out. Also noticed on SPC mesoanalysis that there is an area
of surface moisture convergence associated with the agitated cu, so
it may not take a whole lot else other than the front to set a few
showers off. The good news is that there is a notable inversion just
below 700mb (confirmed by recent AMDAR sounding), so any shower
should actually be capped around 10 k feet. Am debating on adding a
20% chance for a couple of hours around Midnight to account for this
isolated shower potential.

&&

.Short Term...(This evening through Saturday)
Issued at 255 PM EDT Fri Jun 17 2022

A long-awaited break in the heat wave is beginning, but we could
still have some warm and muggy conditions to deal with this
afternoon and evening. Rain-cooled post-MCS regime may not last more
than another couple of hours, and the sfc cold front still lags near
the I-70 corridor.

Not to worry, as the cooler and less humid air will eventually
arrive, given a strong closed upper low diving SE from James Bay to
Maine and a 1028mb sfc high dropping down toward Gitche Gumee. Temps
tonight will run just below climo but the drop in dewpoints will be
gradual through the night. Chamber of Commerce weather is expected
on Saturday with lots of sunshine, temps just barely touching 80,
and dewpoints crashing into the 40s in some locations. Decent
pressure gradient on the periphery of the high will give us a fairly
fresh NNE breeze, with 20-25 mph gusts at times.

.Long Term...(Saturday night through Friday)
Issued at 315 PM EDT Fri Jun 17 2022

Saturday Night and Sunday...

The beginning of the extended period will kick off with seasonable
temperatures and comfortable dewpoints as surface high pressure over
the Great Lakes region provides cool and dry northeasterly flow to
the Ohio Valley. Mid- and upper-level NW flow will be present as an
upper-level trough will be located along the east coast of North
America with an amplified ridge present across the center of the
continent. Temperatures Saturday night will fall into the 50s across
the area as mostly clear skies and light winds allow for enhanced
radiational cooling. During the day on Sunday, expect mostly sunny
skies with temperatures topping out in the upper 70s and low-to-mid
80s.

Monday - Thursday...

It looks like the break from intense heat will be short-lived as mid-
 and upper-level ridging moves back into the Ohio and lower
Mississippi Valleys for the early-to-middle part of next week. There
is still disagreement between the medium-range guidance suites as to
the extent of the heat wave, especially for Tuesday and beyond. WPC
Cluster Analysis continues to show the ECMWF ensemble members
favoring a stronger 500 mb ridge in comparison to the GFS/CMC
ensembles, which promote a flattening in the ridge during the mid-
week time frame. This difference is also observed in 850-mb
temperature anomaly data, with the EPS Ensemble Situational
Awareness Table suggesting temperatures which could be 3-4 standard
deviations above normal, compared with a 1-2 sigma anomaly in the
GFS+CMC ensemble solutions. Due to uncertainty in the veracity of
the ECMWF solution, will continue to show restraint with temperature
forecasts for next week, keeping temps a few degrees below NBM
guidance for now. This will still leave us with several days of
middle- and upper-90s across the region during the Tuesday through
Thursday time frame, with lows falling into the low-to-mid 70s at
night.

As far as precipitation chances are concerned, PoPs should remain
dry through Wednesday afternoon with the ridge and surface high
pressure in control. If the ridge does break down more (as in the
GFS/CMC solutions), showers and thunderstorms may return to the
picture across southern Indiana and north central Kentucky late
Wednesday into Thursday. However, if the ECMWF solution is borne
out, expect dry conditions to persist through at least Thursday.
This persistent hot and dry weather may lead to flash drought
concerns, especially in areas which received little-to-no rain
today.

&&

.Aviation...(00Z TAF Issuance)
Issued at 749 PM EDT Fri Jun 17 2022

Look for light winds shifting from the NW to N overnight as a
frontal boundary sinks southward through the area. A few to sct
clouds around 4-5 K feet may linger through around midnight or so as
well. By sunrise on Saturday, look for stead NNE surface winds
between 10 and 15 mph, with a few gusts up around 20 mph possible.
Otherwise sky cover looks to be very little, if any, so will carry
SKC.


&&

.LMK WATCHES/WARNINGS/ADVISORIES...
IN...None.
KY...None.
&&

$$

Update...BJS
Short Term...RAS
Long Term...CSG
Aviation...BJS



Area Forecast Discussion

National Weather Service Reno NV

 215 PM PDT Fri Jun 17 2022

.SYNOPSIS...

Gusty winds will begin to weaken tonight as a cold front pushes
away from the region. Expect below average temperatures with
chances for showers and thunderstorms tonight across NE California
and again Saturday afternoon. Skies clear, winds relax and
temperatures return to above average territory for next week. The
long-range pattern shows signs of remaining active, with
temperatures near to below normal.

&&

.SHORT TERM...

Another gusty one out there today with max gusts generally
reporting 45-55 mph across the Sierra and W.Nevada. A few wind
prone areas near Hawthorne and Walker Lake registered a peak gust
of 67 mph this morning. Winds will be on the downtrend through the
evening as strongest gradient with the cold frontal passage
shifts eastward overnight.

As the core of the upper low drifts across the NE California and NW
Nevada, there will be enough instability and forcing to pop isolated
showers and thunderstorms across northwestern Lassen County
tonight with isolated to scattered coverage possible through
Saturday afternoon. Precipitation chances will expand south and
east through the Sierra and far western Nevada with about a 15%
chance for isolated storms Saturday afternoon.

Otherwise, expect a cool weekend with high temperatures on
Saturday remaining in the mid to upper 60s across western Nevada
and mid-50s for Sierra valleys. Overnight lows will also cool with
upper 30s to lower 40s for W.NV valleys and upper 20s to lower
30s for Sierra valleys Saturday night into Sunday morning. Fuentes


.LONG TERM...Sunday Onward...

Copious amounts of sunshine should breakout across the Sierra and
western Nevada on Sunday with only an errant cumulus cloud
hanging about the higher mountain elevations in the afternoon.
Lighter but steady breezes from the north-northwest will, however,
keep temperatures on the cool side (10-15 degrees below average)
region-wide with daytime highs in the 70s for lower valleys and
50s and 60s for Sierra valleys.

Light winds swinging more from the east on Monday will continue to
dampen warming across the region. But temperatures will still get
a chance to warm slightly to just below seasonal values with 60s
and 70s for most areas. Daytime highs A few lower valley
locations in the Basin and Range will even tease the low 80s.

Drier and much warmer will best describe conditions starting Tuesday
with more normal June temperatures in the 90s rising up for the
occasion by midweek and continuing into the weekend. Not a bad way
to start the beginning of summer….right? It would be advised to
once again break out the sunscreen and keep it handy for the
interim to come. An errant weak short wave trough stretching SW-NE
across Nevada could bring brief periods of mid and high level
clouds at the start of this forecast period, but upper ridging
will claim greater influence over the region through the later
half of next week. With the warming trend in place, more typical
westerly afternoon Zephyr winds should return by Wednesday and
continue through Friday with possible gusts to 25-30 mph. Blended
guidance does hint at some wind amplification on Thursday and
Friday as a weak short wave lifts northeast across the northern CA
and NV.

Uncertainty abounds beyond Friday as model guidance gives mixed
messages. European ensemble guidance favors a deepening trough
dropping into the Pacific Northwest with unseasonable conditions.
But GFS ensemble guidance desires to strengthen a more seasonable
dry, stable southwest upper flow over the Sierra and western NV
going into the weekend. -Amanda

&&

.AVIATION...

Winds:

* Expecting strong west-southwest wind gusts at all area terminals
  today from 18Z today-04Z Saturday.

* KSVE: Gusts 30-35 kts.
* KRTS-KRNO-KLOL-KTRK-KTVL: Gusts 35-40 kts.
* KCXP-KNFL-KMEV-KBAN: Gusts 45-50 kts.
* KHTH-KMMH: Gusts 50-60 kts.

Low-Level Wind Shear:

* Greatest threat over and east of the central Sierra (KTVL-KBAN-
  KMMH) from 03Z-12Z Saturday with the strongest shear in the lowest
  2000 ft AGL of 22045KT.

Turbulence:

* Latest turbulence guidance suggests the possibility of moderate to
  severe turbulence (both CAT and MTN WAVE) above FL100 for all
  aircraft sizes through 19Z Saturday.

* Turbulence will also be possible near any thunderstorms that
  develop from 00Z Saturday-06Z Sunday across northeastern
  California and from 09Z Saturday-06Z Sunday across the north-
  central Sierra and western Nevada.

Blowing Dust:

* Blowing dust may limit surface visibility down to 1/4 to 1 SM and
  slantwise visibility across the Basin and Range of central-western
  Nevada through 04Z Saturday.

* Blowing dust will primarily affect KNFL-KLOL-KWMC-KBAM.

Shower and Thunderstorm Potential Tonight through Sunday:

* Showers and isolated thunderstorms are possible across northeast
  California and far northwestern Nevada from 00Z Saturday-03Z
  Sunday. These chances will move further south into the central-
  northern Sierra and western Nevada from 09Z Saturday-06Z Sunday.

-Johnston

&&

.FIRE WEATHER...

A dry cold front with a very dry air mass continues to filter in
across NW Nevada this afternoon. This dry air mass is registering
sub-zero dewpoints along with wind gusts in the 25-35 mph range
roughly northward of I-80 in W.Nevada. Stronger wind gusts (35-45
mph) will continue farther south across Mono-Mineral counties
closer to the low pressure center. Winds will begin to weaken
through the evening and overnight as the low shifts eastward.

There will be potential for showers and possibly a thunderstorm
or two from late tonight into early Sunday for areas along the
Sierra and northward into Lassen and Washoe counties. 5-10%
chance for wetting rains (>.10") along the Sierra. Best potential
for thunderstorms to develop will be Saturday afternoon/evening
across Lassen county with a 25-30% chance and about a 15% across
the Sierra and Sierra Front. Fuentes/Edan

&&

.REV Watches/Warnings/Advisories...
NV...Blowing Dust Advisory until 9 PM PDT this evening NVZ004.

     Wind Advisory until 9 PM PDT this evening NVZ001.

     Lake Wind Advisory until 9 PM PDT this evening for Lake Tahoe in
     NVZ002.

     Wind Advisory until 9 PM PDT this evening NVZ003.

CA...Wind Advisory until 9 PM PDT this evening CAZ073.

     Lake Wind Advisory until 9 PM PDT this evening CAZ071.

     Lake Wind Advisory until 9 PM PDT this evening for Lake Tahoe in
     CAZ072.

&&

$$

For more information from the National Weather Service visit...
http://weather.gov/reno