Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/07/20
Area Forecast Discussion...CORRECTED
National Weather Service Brownsville TX
712 PM CDT Sat Jun 6 2020
.DISCUSSION...Updated the forecast to include a Coastal Flood
Advisory early Sunday morning into the early afternoon. Around
high tide at 8:12 AM CDT, water levels are expected to reach or
even push into the dunes on South Padre Island and Boca Chica
Beach. Driving on the beach is not recommended.
.DISCUSSION...Updated for latest aviation discussion below.
.AVIATION...VFR conditions are expected to persist across Deep
South Texas and the Rio Grande Valley over the next 24 hours. As
Tropical Storm Cristobal moves northward across the central Gulf,
light to occasionally moderate winds are expected through the
period, and will constantly be shifting direction.
.PREV DISCUSSION... /issued 315 PM CDT Sat Jun 6 2020/
SHORT TERM (Now through Sunday Night): Some very light showers
developed across the lower Texas Gulf waters and the immediate
coastline this morning and amounted to trace amounts of rainfall,
mainly in rural locations. As of 2 PM CDT, KBRO shows one lone
shower just north of the BRO coastal waters, moving in a southwest
direction. Isolated showers will continue to be possible, generally
restricted off the coast through this afternoon, but can`t rule out
a stray shower or two inland, with the latest HRRR model suggesting
some isolated, light showers developing along and west of U.S. 281
later this afternoon. Not completely sold on this solution, but did
add some silent 10% PoPs into the forecast through 7 PM. Low
temperatures tonight will drop into the low-mid 70s.
Upper-level ridging will maintain control over Deep South Texas
through the short-term period as Tropical Storm Cristobal continues
to move northward across the central Gulf of Mexico. Subsident air
on the west side of Cristobal should keep the atmosphere dry in the
short-term. However, winds will try to turn easterly during the
afternoon on Sunday, which may produce isolated showers with the
seabreeze. Not a whole lot of confidence of this scenario occurring
with the limited moisture available. Shower activity would be very
spotty, even if this were to occur. Overall, winds will remain light
and variable across the CWA through tomorrow afternoon. Southerly
winds are anticipated to return and prevail starting Sunday night.
Temperatures will really begin to increase beginning tomorrow
afternoon, with highs about 4-6 degrees warmer than today...mid-
upper 90s in most locations, with lower 100s across western Starr
and Zapata Counties.
A Coastal Flood Advisory will likely be needed again for the coastal
portions of Cameron, Willacy, and Kenedy counties tomorrow morning,
when the next high tide occurs. A High Risk of rip currents will
continue at local beaches due to the Cristobal swell. As a result, a
Rip Current Statement is in effect through the weekend. Will
continue to monitor for the possibility of a High Surf Advisory for
LONG TERM (Monday through Saturday): The main issue in the long
term will be the hot to very hot conditions, especially during the
first half of the period. Deep south Texas will remain on the
western periphery of Cristobal, as remnants of this system advances
northward, and under building mid-level ridging. The combination of
hot temperatures and the steady moist southeast surface flow will
allow dew points to increase across the area by early next week
resulting in dangerous high index values. The highest heat indices
are expected Tuesday with widespread values of 110-115+ degrees.
Heat advisories may be possible early to midweek, with the best
chance occurring on Tuesday afternoon. Strong subsidence over the
region will keep rain chances very low to nil.
A weak cold front is expected to arrive late Wednesday into
Thursday. Low level moisture pooling ahead of this front and weak
lift associated with the boundary may support a slight chance of
showers and thunderstorms across the area Wednesday into Thursday.
Temperatures are expected to fall a few degrees, near normal levels,
late in the week courtesy of northeast flow. Much drier air arrives
by Friday as surface high pressure moves into the region.
The concern for minor coastal flooding and the higher risk of rip
currents will gradually diminish early next week once Cristobal
moves farther north after making landfall across the northern Gulf
Coast. However, lingering minor coastal flooding may continue at
least through the morning high tide cycle on Monday.
MARINE (Now through Sunday Night): Buoy 42020 reported north winds
around 10 knots gusting to around 14 knots with seas around 3.5 feet
with a period of 8 seconds at 1340 CDT/1840 UTC. Light to moderate
winds are expected to prevail along the Lower Texas Coast during the
period. However, adverse sea conditions will impact the lower Texas
Gulf waters due to swell propagating from Tropical Cyclone
Cristobal. A Small Craft Advisory will go into effect at 6 PM CDT
this evening and continue through Sunday afternoon for the outer
Gulf waters (20-60 nm). Meanwhile, a Small Craft Advisory will go
into effect at 10 PM CDT tonight and continue into Sunday afternoon
for the nearshore Gulf waters (0-20 nm).
Monday through Thursday): Marine conditions will gradually improve
next week as Cristobal moves farther inland across the northern Gulf
coast on Monday. The relatively tight pressure gradient in the wake
of the tropical system will support moderate south winds Monday into
Monday night. Exercise caution conditions are expected along the
lower Texas Gulf waters during this time. Winds diminish Tuesday
night into Wednesday as the pressure gradient weakens with the
approach of a weak cold front.
TX...High Rip Current Risk through Sunday evening for TXZ256-257-351.
Coastal Flood Advisory from 5 AM to 2 PM CDT Sunday for TXZ256-
GM...Small Craft Advisory until 6 PM CDT Sunday for GMZ170-175.
Small Craft Advisory from 10 PM this evening to 2 PM CDT Sunday
This product is also available on the web at:
Area Forecast Discussion
National Weather Service Charleston SC
1005 PM EDT Sat Jun 6 2020
The area will remain between Atlantic high pressure and a
surface trough inland tonight. A cold front will stall over or
just north of our area early next week, then will gradually
dissipate through the middle of next week. Another weakening
cold front could approach the area late next week, then shift
offshore late next weekend.
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
Isentropic ascent will continue to produce widespread rains
associated with Tropical Storm Cristobal that will continue to
inch northward across the Altamaha River overnight. The rains
will only make it so far north, prevented from spreading much
any further north than maybe I-16, if even that far north. We
show a tight gradient from little to no PoP north of I-16, to as
much as 40-60% to the south of there. Not certain on how much
t-storm activity there will be, so removed it from all but
McIntosh County where there might be just enough MLCAPE.
The HRRR is hinting at a small convective band developing from
off the Gulf Stream after 4 or 5 am, and making a run toward the
South Carolina coast. This will bear watching.
Given extensive cloud cover and the elevated dew points, it`ll
be another warm and muggy night. Lows will average several
degrees above climo.
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
Sunday: Mid-level heights should remain consistent overhead as TC
Cristobal moves into a ridge of high pressure over the MS Valley. At
the surface, focus will be on TC Cristobal approaching the Gulf
Coast. Abundant moisture on the eastern side of the storm will be
ushered across the Southeast, with PWATs in the 1.5-2" range. At the
same time, a weak cold front will approach from the north, stalling
over or just north of our area. The combination of the abundant
moisture and increasing lift will lead to showers. The highest POPs
are over our GA counties where moisture is slightly higher. There is
not much instability, so the thunderstorm risk during the day is
low. Despite plenty of clouds, highs are still expected to reach the
mid to upper 80s. The showers are expected to dissipate in the
evening and overnight with the loss of daytime heating. Lows will
remain mild, ranging in the low to mid 70s, warmest at the beaches.
Monday and Tuesday: The mid-levels will consist of Cristobal moving
to the north towards the Great Lakes region, eventually becoming
absorbed in an approaching trough to the west. This will push a
ridge of high pressure to the east, over the East Coast. At the
surface, Cristobal will be moving inland far to our west while a
weak front will be dissipating over or just north of our area. Deep
moisture originating from the Gulf of Mexico will remain across the
Southeast, with PWATs still in the 1.5-2" range. Most of the
precipitation should be driven by the afternoon heating. We kept the
chance POPs each afternoon, with lower POPs at night. There is a
more instability both days, leading to greater probability of
thunderstorms. The main concern is locally heavy rainfall due to the
slow storm motions. Though, damaging wind gusts cannot be ruled out
if DCAPE values increase. Highs should be in the upper 80s to near
90 degrees each day. Lows will remain mild, ranging in the low to
mid 70s, warmest at the beaches.
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
Sfc high pressure will gradually spread across the region from the
western Atlantic mid-week under a ridge of high pressure aloft. This
should shift the bulk of deeper tropical moisture inland while the
remnants of Tropical Cyclone Cristobal continues to lift north and
eventually becomes absorbed in a longwave trough of low pressure
advancing across the Central United States. Few to scattered showers
and thunderstorms remain in the forecast Tuesday night through
Wednesday, but the bulk of precip activity should be more diurnally
driven with peak coverage Wednesday afternoon. Latest guidance then
suggests a weakening cold front approaching inland areas Thursday
and potentially stalling over or near the area into Friday before a
reinforcing cold front approaches inland and shifts offshore during
the weekend. Given the setup, scattered showers and thunderstorms
are forecast each day, before the bulk of precip shifts offshore
with the front late Saturday. Afternoon highs should remain near
normal throughout the week given precip activity and some clouds in
place. In general, highs should range in the mid/upper 80s (warmest
away from the coast). Overnight lows will start off mild Wednesday
night, ranging in the low/mid 70s, then become cooler by the weekend
behind any fropa, ranging in the mid/upper 60s inland to lower 70s
along the coast.
.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
KSAV: VFR ceilings as we begin the 00Z TAF cycle, but MVFR
ceilings, potentially even IFR, are expected after 06Z, as
moisture increases within a S-SW low level flow. Ceilings should
increase into the low-end VFR range after 15Z.
The bulk of the -RA/-SHRA associated with Tropical Storm
Cristobal will stay south of the terminal until late Sunday
morning into the afternoon. Even so, any sub-VFR visibilities
seems highly unlikely.
KCHS: VFR will prevail with the 00Z TAF.
Extended Aviation Outlook: Brief flight restrictions are possible
due to showers/thunderstorms, especially each afternoon/evening.
Overnight: The pressure gradient is starting to slacken, and
we`re looking at narrow ridge between the cyclonic circulation
around Cristobal and trough to the N-NW. This will result in S
or SW winds around 15 kt or less, with seas generally at or
below 3 or 4 ft.
A cold front will stall over or just north of our area on
Sunday, then gradually dissipate into the middle of the week.
Winds/seas are expected to remain below Small Craft Advisory
levels. High pressure should then pass offshore midweek before a
weakening cold front approaches inland areas Thursday.
Winds/seas are expected to remain well below Small Craft
Advisories during this time frame with onshore winds generally
remaining at or below 10-15 kt while seas build no higher than
Lingering affects of the recent lunar perigee and full moon will
continue to contribute to elevated tides into early next week. Minor
coastal flooding will be possible during the evening/nighttime high
tides along the South Carolina coast.
The KCLX radar will remain out of service for equipment upgrades
through June 11, and radar data will not be available during this
time. Neighboring radars include: Wilmington, NC (KLTX);
Jacksonville, FL (KJAX); Moody AFB, GA (KVAX); Warner Robins AFB, GA
(KJGX); and Columbia, SC (KCAE).
Supplemental weather balloon releases in support of Tropical
Cyclone Cristobal forecasts will end at 06Z tonight (6/7).
Area Forecast Discussion
National Weather Service Grand Forks ND
1012 PM CDT Sat Jun 6 2020
Issued at 1008 PM CDT Sat Jun 6 2020
Showers continue over far NE ND and thru much of nrn MN in broad
area of 700 mb warm/moist advection. No thunder noted.
Attention turns to line of storms with a long history of winds
over 60 mph that moved thru parts of Wyoming and Colorado earlier
and now moving north-northeast 60 mph thru NW SD into SW ND.
Severe t-storm watch for far western fcst area, but as discussed
with SPC uncertainity in regards to how long the high wind
potential will last as it will outrun the 50-60 kt 850 mb jet
which...and instability will become increasingly elevated. HRRR
past couple runs have area of t-storms increasing in width and
less of a line as it moves into central ND past Bismarck and
therefore less wind threat.
.SHORT TERM...(This evening through Sunday night)
Issued at 221 PM CDT Sat Jun 6 2020
This afternoon and evening... A line of rain showers continues to
moves across eastern North Dakota and northwest Minnesota this
afternoon. There is very little instability in the environment
the lines is moving into so thunderstorms are not expected. There
could however still be an isolated thunderstorm farther south in
the Red River Valley where the atmosphere is more unstable.
Saturday night into Sunday morning... Later tonight additional
thunderstorm development is expected as a shortwave moves into the
Northern Plains. A strong LLJ combined with high precipitable
water ranging from 1 to 1.5 inches will provide an environment
favorable from rain. When combined with MU CAPE values between
1500 and 2500 J/kg and bulk shear values around 50 knots some
strong to severe thunderstorms are also expected. While the best
chances for significant severe convection remains to the south and
west in western ND and SD some of these storms could continue
into eastern North Dakota and northwest Minnesota overnight. If
these storms do make it this far north and east they will likley
be in some form of linear system or MCS with wind as the main
threat. With the high precipitable water heavy rain will also be a
threat, but with dry soils the main flooding threat would be in
Sunday afternoon into Sunday night... An hot an moist environment
will be present with temperatures in the upper 80s and low 90s
combined with precipitable water values in the 1 to 1.5 inch
range. These precipitable water values are between the 90th
percentile and max in NAEFS R-Climate so this is a very moist
environment for this time of year in the Northern Plains. Hot and
moist conditions lead to high instability and CAPE with MU CAPE in
some CAMs reaching well into the 4000 to 5500 J/kg range. This
unstable environment combined with an approaching warm front and
bulk shear of 40 to 60 knots creates an environment favorable for
all modes of severe weather. The high CAPE environment helps lead
to high hail index values suggest large hail will be possible.
With surface to 1 km SRH also high in the 200 to 300 m2/s2 range
and generally low LCLs tornadoes will be possible. Also with the
environment favorable for supercells very high winds will also be
a threat. There have been some variations between different
ensemble systems and CAMs to there remains some doubt as to where
the greatest chances will occur in our region. There is enough
confidence however to state the thunderstorms, likely severe, will
be present on Sunday and into Sunday night.
.LONG TERM...(Monday through Saturday)
Issued at 221 PM CDT Sat Jun 6 2020
Monday-Saturday...Model guidance in decent agreement with the
overall pattern, with southwest flow aloft gradually transitioning
to northwest flow aloft and then ridging toward the weekend. Active
weather to start the period will become much quieter (drier) by mid-
week into the weekend. Temperatures will also be much cooler. With
that all said, the most uncertainty exists at the beginning half of
the period as the track of the tropical depression will dominate
what happens across this region. The main impacts will be severe
thunderstorm potential Monday afternoon, and then heavy
rain/excessive rainfall potential into Tuesday. The 12z ECMWF tracks
the tropical depression further west (and brings more rainfall
further west) compared to other guidance. Although this is still an
outlier scenario, it indicates the uncertainty that still exists. At
any rate, a strong baroclinic zone with a cold front pushing
eastward will bring severe thunderstorm chances Monday evening
(where the front is set up), and then a prolonged period of moderate
precipitation into Tuesday (with the area and duration of the
moderate precipitation dependent on the track of the tropical
depression). Excessive rainfall potential will also be dependent on
what happens before Monday (if heavy rainfall saturates the soils).
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 713 PM CDT Sat Jun 6 2020
A series of convective rain bands will work across the FA from
southwest to northeast during the early evening... in advance of
stronger convection expected during the overnight period. Generally
VFR conditions are expected outside of showers this evening, with
southeast surface winds gusting from 15 to 30 kts. During the
overnight period and into early Sunday morning expect more
widespread showers and thunderstorms with areas of MVFR conditions
in heavy rain and strong gusty winds. This should lift through
eastern ND from 06z through 10z, and through northwest and west
central MN from 09z through 15z.
Additional strong to severe thunderstorms are possible again late
Sunday afternoon into the early evening.
Area Forecast Discussion
National Weather Service Glasgow MT
749 PM MDT Sat Jun 6 2020
Severe thunderstorm watch is up for most of the area until
midnight MDT. Made an attempt to time the progression of the rain
as it moves across the area this evening and tonight. While the
greatest instability is well to our east, looking at the HRRR
updraft helicity swaths it looks like it could be a long night
across the CWA. Meanwhile, the RAP wants to turn up the 850mb
winds overnight in the eastern CWA, too.
With 1.22" on the 0z sounding breaking the previous 0z June 7
daily max (was 1.17" from the SPC`s Sounding Climatology Page),
felt ok with adding heavy rainfall qualifier to the forecast
Now, it`s wait-and-see time: we`re primed for a lot of rain, wind,
Majority of the larger changes to the forecast took place with the
first 3 days of the forecast. With the tonight period having the
heavier edits. Temperatures were trimmed back several degrees for
this afternoon with the stratus shield having no end in sight
looking south. In fact, radar echos that were previously not in
several locations of the model data have begun forming up in the
stratus bands. This diabatic cooling effects may be able to
further remove the edge from any surface based storms that happen
this evening. If a mid-level jet kicks in later this evening there
may be a possibility for elevated convection with a few severe
characteristics due to higher bulk shear. But, CAPE with
successive runs of the NAM Soundings has been in rapid decrease
and becoming a far more skinny profile for many points in
northeast Montana. So, there`s much less potential lift energy to
work with now.
Sunday through Monday: With flow aloft turning southwest showers
with a few thunderstorms will remain in the forecast through
Monday. Temperatures will drop on Monday and this trend should
maintain through mid-week though shower chances leveling off
some in that same mid-week time frame. GAH
Update for morning hours was limited to blending in satellite and
surface wind fields into the next 6 hours. Looking at an
assessment for later today, large stratus-shield exists across
eastern Montana into northern Wyoming and this is having a strong
decreased affect on insolation. Current NAM doesn`t even mix out
the lower inversion completely for today till 6PM due to the loss
of radiational heating from Glasgow to Glendive. This produces a
large cap that will need to be eroded into the evening before
storms can get going. With the loss of surface heating to couple
up with mid-level lift, storms are more likely to become elevated
and less organized through the early evening with peak severe
threat probably occuring around 5 to 9PM if there is severe at
all. HREF Updraft helicity is also appearing to put only weak
rotation with storms at these times. GAH
A thunderstorm from higher terrain over central Montana had moved
across the northern counties of Northeast Montana last night that
produced quarter sized hail and strong winds over north central
Valley county. The storm had fragmented into an established
cluster of pulse storms that are currently situated over the
northeastern counties and are expected to stick around until later
this morning with the low level jet.
The upper ridge is headed east this morning as a low pressure
system to the west, along with a shortwave from the southwestern
US, moves into northeastern Montana today. A surface pressure
gradient is currently oriented over the area and is expected to
tighten as the low approaches. Some mesonet observations are
reporting gusty winds this morning with widespread 40 knots with a
couple gusting to the upper 50s kts at Beaver Hill and pushing 70
kts at Sioux Pass. Expect winds to increase this morning and
gusty winds will persist throughout the day. The Lake Wind
Advisory has been extended until 11PM.
The low is expected to arrive by the early afternoon from the
southwest and warm frontal precipiation chances will begin to
increase as it treks northeastward. Low to midlevel southeasterly
wind will draw moist air into the Yellowstone River Valley.
Temperatures last night remained warmer than expected and with
many models having temperatures in the lower 80s, the GFS is
slightly warmer and the RAP is much more ambitious with highs into
the 90s. Dew points are slow to increase, but may get into the 60s
later today. Plenty of instability with CAPE values from around
1000 to 2000 J/kg. Some dry slotting from the south late today
and a stubborn inversion cap will slowly erode and may delay
thunderstorms into the early evening and overnight hours. Once
thunderstorms are able to initiate, they could potentially become
severe with large hail and damaging winds. The highest all hazard severe
potential will be more likely in the southeastern corner. Will
plenty of available moisture and precipitable water to around an
inch or more, any strong to severe thunderstorms could produce
locally heavy downpours and concerns for flash flooding. Any
camping and recreation on the lake can be hazardous today due to
gusty winds in addition to hazards associated with severe
thunderstorms that develop.
There will be brief break from precipitation Sunday morning
followed by a cold front that will bring another round of showers
and thunderstorms, some severe south of the Missouri River and
along the Yellowstone River Valley. These storms however, are not
expected to be as energetic as the storms expected later today. Lingering
showers and thunderstorms will be possible through Monday
A ridge will emerge again around midweek bringing dry weather and
seasonal temperatures. A low may follow along at the end of the
LLWS: There is a chance for low level wind shear from 03 to 12Z
tonight at KSDY and KGDV.
FLIGHT CAT: VFR - MVFR
DISCUSSION: Look for increasing chances for widespread
thunderstorms in the late afternoon that will last through the
overnight hours. A low pressure system will be responsible for
the shift in winds tonight. MVFR conditions will be possible with
storms this evening into overnight from 03 to 15Z at KGGW and KOLF
WIND: E-SE 10-20 kts with higher gusts (especially near storms)
shifting to the W-SW by sunrise. W-SW winds on Sunday 10-20 kts,
decreasing to 5-10 kts late in the day. W-NW winds 5-10 kts on
Lake Wind Advisory until noon MDT Sunday For Fort Peck Lake for
Central and Southeast Phillips...Central and Southern Valley...
AREA FORECAST DISCUSSION
National Weather Service Hastings NE
718 PM CDT Sat Jun 6 2020
.SHORT TERM...(This evening through Sunday)
Issued at 247 PM CDT Sat Jun 6 2020
Convection from this morning has pretty much dissipated with the
decrease in speed of the low-level jet as it moved out of the CWA.
We are squarely in the warm sector and although we decouple
somewhat, we will still retain a bit of a gust out of the south.
Went more toward CONSRAW for lows, which keep up temps a bit.
With the theta-e ridge nearby, I was a little hesitant to go
completely dry tonight, considering what happened this morning, so
I did go with some small POPs in our west late tonight. There is
enough MUCAPE for severe weather, favoring marginally severe
hail if anything.
CONSMOS and RAP wind gusts support quite a windy day as soundings
indicate steepening low-level lapse rates. Wind gusts of at least
40 kts will be probable for much of the CWA.
.LONG TERM...(Sunday night through Saturday)
Issued at 247 PM CDT Sat Jun 6 2020
One big issue for the long term is for Monday afternoon and night
as the cold front approaches. The slow movement of this front may
encourage training of cells, which could lead to some localized
flooding. Severe storm parameters could give us some severe
weather as well.
The other notable issue will be the cool-down behind the front as
numerical models are consistently indicating an anomalously cool
period during mid week. Cool and possibly cloudy conditions with
strong cold air advection for this time of year, could have us
struggling to get into the 70s for highs on Tuesday.
Upper level ridging will keep the forecast dry from Wednesday
afternoon through the rest of the long term forecast, with
temperatures on a mild warming trend toward the end of the
forecast time frame.
.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Monday)
Issued at 643 PM CDT Sat Jun 6 2020
The primary aviation concern will continue to center around the
strong low level wind shear that is expected to develop this
evening as the low level jet strengthens and will persist until a
few hours after sunrise. Most of the thunderstorms should remain
west and northwest of our TAF sites tonight, but will have to keep
an eye on how thunderstorms track across the area tonight.
Sunday will be another windy day across the region. VFR ceilings
and visibilities are expected to continue.
Area Forecast Discussion
National Weather Service Jacksonville FL
750 PM EDT Sat Jun 6 2020
The region will be between high pressure to the east, and tropical
storm Cristobal over the central Gulf Tonight. Moisture will
continue to stream into the region between these features. Heavy
rainfall, which could lead to localized flooding, will continue to
be a possibility through the night especially inland NE FL. A few
strong to severe storms possible as well. Have had a few cells
with rotation in them this afternoon, and expect this potential to
continue, so can not rule out an isolated tornado.
[Through 00Z Monday]
Widespread rain with embedded thunderstorms expected through this
period with restrictions.
.PREV DISCUSSION [313 PM EDT]...
.NEAR TERM [through Sunday]...
A flash flood watch has been issued through Sun evening for our
western FL zones as widespread moderate to locally heavy rainfall
overspreads NE FL from the south. Deep tropical moisture will
remain in place (PWAT 2.5") with the area on the east side of TS
Cristobal as the storm approaches the LA Gulf Coast through Sun
afternoon. Waves of moderate to heavy rainfall with isolated
embedded tstorms will continue to pivot northward into the evening,
then tonight anticipate a more solid band of moderate to heavy
rainfall developing across north Florida as low level convergence
increases between a lifting frontal zones across south -central
FL and a persistent low level ridge axis holding firm just north
of the Altamaha River basin. This ridge will limit the northward
extend/expansion of the convective band into Sun, and generally
focus a W-E oriented swath of heavy rainfall generally near and
south of the I-10 corridor late tonight into Sunday morning.
Please refer to the below `Hydrology` section for rainfall
outlook. Ridge strengthens north of the Altamaha Region Sun
afternoon, shunting corridor of heavy rain SSW toward the I-75
corridor of NE FL with drier mid level air (700-500 mb) decreasing
rain chances across SE GA and eastern NE FL into Sun evening.
In addition to heavy rainfall potential, there will be a low
tornado threat for NE FL into the evening with elevated 0-1 km
shear values 20-25 kts with low level ESE winds under increasing
SSW winds out of the GOMEX, with speeds increasing to 35-45 kts at
850 mb through 06z.
Cloudy skies, and warm humidity ESE to S flow will continue into
with daytime highs below normal in the 70s to low 80s and muggy
nighttime lows in the upper 60s to low/mid 70s.
.SHORT TERM [Monday through Tuesday]...
Mon...A weak pressure pattern in place across the local area as
the remnant low of Cristobal tracks northward across the lower MS
river valley and the 1000-700 mb ridge centers builds from the
Bahamas Mon and then over N FL into Tuesday. A ribbon of tropical
moisture (PWAT over 2") will rotate across our GA zones and toward
the Atlantic coast into Mon evening as steering flow weakens and
back slightly SSW between the low to our WNW and the ridge to the
SSE. This pattern will shift morning convection across our western
Gulf Coast zones across SE GA and toward the Atlantic coast into
the afternoon and evening. Main convective hazard will be locally
heavy rainfall with deep moisture and slow motion over the region.
High temperatures will trend below normal in the low/mid 80s with
muggy lows in the 70s.
Tue...Very slow storm motion under the mean layer 1000-700 mb
ridge and lingering high moisture (PWAT 1.8-2 inches) will
continue high rain chances over the local area, but with a more
diurnal sea breeze regime expected with both sea breezes
developing along the Atlantic and Gulf Coast, merging inland
between Highway 301 and I-75 into the late afternoon and early
evening. Very warm temps aloft with lack of strong forcing will
limit severe storm strength, but will continue the localized heavy
rainfall threat and increase the potential of convective wet
downbursts in stronger cells given more diurnal instability.
Temperatures will warm into the low 90s inland given less morning
cloud cover. Precip will gradually fade in coverage inland and
intensity into Tue night with linger clouds keep lows mild in the
low 70s. An approaching weak front from the NE will maintain a low
chance of mainly coastal showers and isolated tstorms through Wed
.LONG TERM [Wed through Sat]...
Wed & Thu...Elevated rain chances continue across the local area
with deep tropical moisture (PWAT over 2") lingering over the
region. A `backdoor` cold front/trough axis is expected to shift
inland along the local Atlantic coast early Wed, with morning
showers and isolated tstorms shifting inland into the afternoon
and evening hours. This trough axis will converge with a southward
moving trough across GA Wed night into Thu, with elevated rain
chances continued across SE GA into Thu morning. A passing mid
level short wave trough will enhance convection across inland
areas Thu afternoon into Thu evening with a few stronger storms
possible given the enhanced forcing aloft with the main t`storm
hazards this period localized flooding rainfall potential and wet
downbursts due to precip loading. High temperatures will trend
near to below normal in the low/mid 80s given abundant cloud cover
and rain chances this period. Low temperatures will trend near to
above normal in the 70s.
Fri & Sat...Drier air finally begins to filter across the region
from the WNW as a mean layer mid/upper level trough deepens across
the eastern CONUS. PWAT content returns back toward climo values
in the 1.4.-1.6 inch range Fri with the linger surface front
across south GA. This front, combined with forcing from the sea
breezes and cooler temps aloft in the -7 to -9 degC range under
the deepening upper trough could bring a better chance of a few
stronger storms especially during the afternoon and evening,
although overall storm coverage will trend downward. Most
convection fades Fri evening with loss of diurnal heating,
however, a low chance of precip will continue across SE GA through
Sat morning where surface front will finally begin to edge farther
south. Sat morning into Sat afternoon, the front is expected to
shift south across NE FL with a drier airmass expected Sat night
as PWAT content falls below normal values (less than 1 inch)
trailing the frontal passage with a deep layer WNW flow over the
local area. High temperatures will trend back toward normal values
in the upper 80s to near 90 as deep moisture decreases with low
temperatures generally cooling back toward normal values in the
mid 60s inland to low 70s coast.
Tropical Storm Cristobal will track northward toward the central Gulf
of Mexico Coast through Sunday with high pressure offshore of the Florida
Atlantic coast. Widespread rain with embedded thunderstorms will impact
the local waters through Sunday. South winds will increase tonight
and Sunday to marginal Small Craft Exercise Caution levels over the
outer waters with speeds 15-20 kts. Headlines are not expected beyond
Sun night with an extended period of SSE winds expected. High pressure
builds across south Florida Monday and Tuesday. A weak trough will
move across the local waters from the east Wednesday and merge with
a front across south Georgia. This front will linger across the region
Thursday and Friday.
RIP CURRENTS: Low Risk SE GA beaches today. Moderate risk NE FL
beaches today. Moderate risk for all beaches expected Sunday. Low
to marginally moderate risk of rips expected Mon-Tue given weak
winds. Elevated rip current risk returns Wed due to stronger
Persistent moderate to heavy rainfall with isolated embedded
thunderstorms will move south to north across the forecast area
through tonight and linger into Sunday across NE FL with low
daytime dispersion due to light winds and cloud cover. Rainfall
accumulations will generally range from 3-5 inches across NE
Florida through Sunday afternoon, with isolated higher amounts.
Rainfall amounts decrease across southeast Georgia with less than
1 inch total expected near the Altamaha River basin. Warmer, moist
southerly flow continues Monday with the highest coverage of
showers and storms in the afternoon.
Persistent, moderate to heavy rain shield will overspread the
local area from south to north through Sunday morning. Latest
consensus guidance continued to indicate widespread rainfall
totals through the next 24 hrs of 2-4 inches mainly south of the
I-10 corridor with locally higher amounts certainly possible
especially across the Suwannee River Valley and near the I-75
corridor. Recent CAMs including the HRRR, RAP and Nested NAM have
localized 6-9 inches through midday Sunday across parts of the
Suwannee River Valley. Issued a Flood Watch for our western tier
FL zones through Sunday evening, with localized flooding potential
for vulnerable urban areas including Jacksonville, Orange Park
and St. Augustine.
.PRELIMINARY POINT TEMPS/POPS...
AMG 70 80 72 88 72 / 60 70 30 70 20
SSI 73 79 74 86 75 / 70 70 30 50 20
JAX 71 79 72 89 74 / 90 90 30 60 20
SGJ 72 77 72 87 73 / 90 90 40 60 20
GNV 72 79 72 88 72 / 90 90 60 70 20
OCF 73 80 72 88 72 / 90 90 60 70 20
FL...Flash Flood Watch through Sunday evening for Central Marion-
Eastern Alachua-Eastern Marion-Gilchrist-Hamilton-Northern
Columbia-Southern Columbia-Suwannee-Western Alachua-Western
Area Forecast Discussion...UPDATED
National Weather Service North Platte NE
621 PM CDT Sat Jun 6 2020
.SHORT TERM...(This evening through Sunday night)
Issued at 233 PM CDT Sat Jun 6 2020
The thunderstorm forecast tonight and again Sunday afternoon follows
the short term model blend plus the NAMnest which was fairly
aggressive with the storm activity advancing east through wrn
Nebraska tonight and redeveloping farther east and south Sunday
A few strong to severe storms formed this morning and this afternoon
in the warm sector along and north of a advancing warm front. This
storm activity will lift north into SD this afternoon and present a
strongly capped atmosphere across much of ncntl and southwest
Nebraska tonight. The forecast allows for isolated severe storms
in the warm sector across swrn and ncntl Nebraska this afternoon
and this evening.
One or two clusters of strong to severe storms should move
through western Nebraska late this afternoon and this evening also.
The CAMS and SPC suggests wind damage and large hail will be the
primary threat. This storm activity should begin to weaken around
03z this evening. The CAMs show storm motions of 60 mph but the
RAP model soundings show the Bunkers right moving storm motion
much slower near 35 mph and just the left moving storm motion near
All of this storm activity should begin to weaken around 03z this
evening according to the NAMnest and redevelop Sunday afternoon
farther east near highway 83. The forecast leans on the NAMnest
Sunday afternoon allowing for storms to form south of Interstate
80 across swrn Nebraska. This storm activity should also weaken
early in the evening Sunday. This forecast is close to the SPC day
two severe weather outlook. Wind fields aloft relative to the
instability appear to be quite strong across srn Nebraska
suggesting isolated storm development there. To the north, MLCAPE
near 3000J/KG and midlevel winds around 50kts will support
.LONG TERM...(Monday through Saturday)
Issued at 233 PM CDT Sat Jun 6 2020
WPC suggested a flood risk across ncntl Nebraska Monday
associated with a stalled Pacific cold front, strong winds aloft
and precipitable water near 1.5 inches. The key to this forecast
would be the location of the front which could be a bit farther
east or west depending on the upper level forcing and convection
events tonight and Sunday. SPC suggested a severe weather threat
in the same area. Storm development is possible ahead, along and
behind the front.
This weather system should be clear of wrn and ncntl Nebraska with a
continued chance of showers and thunderstorms associated with cold
air aloft. The forecast Wednesday through Saturday is dry.
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 620 PM CDT Sat Jun 6 2020
A powerful squall line underway across Wyoming and Colorado this
evening will sweep into wrn Nebraska and weaken near highway 83
VFR is expected from 08z tonight through 21z Sunday across all of
wrn and ncntl Nebraska.
Isolated to scattered thunderstorm development is expected along
and near highway 83 beginning 21z Sunday.
Area Forecast Discussion
National Weather Service Louisville KY
957 PM EDT Sat Jun 6 2020
Issued at 955 PM EDT Sat Jun 6 2020
Tranquil conditions exist across central KY and south-central IN at
this time. Earlier convective band over eastern KY that almost
clipped Nicholas County has moved away. Expect a clear/mostly clear
night. Latest ASOS and KY Mesonet obs show a muggy late evening in
process with surface dewpoints still in the upper 60s to mid 70s,
but drier air is now infiltrating northern KY and extends back into
central IN. Lower dewpoint air will gradually sink into our northern
forecast area overnight, although higher dewpoints remaining over
south-central KY could cause patchy fog, especially in river
valleys. Current forecast handles this well. Expect quiet weather
With surface high pressure across the upper OH Valley on Sunday,
expect a nice weather day - quite warm but a little cooler than
today plus noticeably lower humidity, plenty of sunshine, and an
east to northeast breeze. Enjoy the day.
.Short Term...(This evening through Sunday)
Issued at 300 PM EDT Sat Jun 6 2020
Temperatures have climbed into the upper 80s and low 90s across the
area, under mostly sunny skies. SDF has reached 92 so far, with a
couple hours of heating still possible. 94 is the record at SDF from
2008, and it is not out of the question that we can tie that.
BWG/LEX records won`t be reachable today.
Otherwise, the only other thing worth mentioning is that there is
still a slight chance of a brief shower or storm in our far NE/E CWA
between 7-9 PM EDT. The HRRR has been consistent showing development
there early this evening, and given a pretty unstable airmass (2500-
3000 J/KG) amidst a weak cap think there is enough confidence to
keep the small/short-lived pop there. In addition, there appears to
be a weak wave dropping SE through our area around the time.
Upstream over eastern IL/western IN a few showers have popped amid
what appears to be a batch of ACCAS on satellite imagery. These are
associated with some slightly steeper mid level lapse rates (SPC
mesoanalysis) and this could be just enough of a trigger in our NE
around the time the HRRR also suggests some brief activity.
Expect a clear and dry overnight into Sunday with slightly "cooler"
temps topping out in the low to mid 80s in most spots. Temps around
90 are still possible down by BWG. There will also be a notable drop
off in dew points, especially across the northern CWA where some
upper 50s will feel quite nice compared to the low 70s Td`s we had
Lastly, did put some patchy fog for late tonight/Sunday morning down
around Lake Cumberland where low level moisture won`t be as scoured
out by the weak front. Look for lows in the low 60s north to upper
60s south tonight.
.Long Term...(Sunday night through Saturday)
Issued at 302 PM EDT Sat Jun 6 2020
Fair weather continues Sunday night and Monday with a 591 dam mid
level ridge building east over the Ohio Valley. Sfc high pressure is
forecast to drift from the Great Lakes to Mid-Atlantic. Meanwhile,
Cristobal will begin to accelerate and move NNW over Louisiana and
Arkansas on the western periphery of the ridge. Skies Sunday night
will remain clear over our neck of the woods with lows in the low to
mid 60s. The cirrus shield from the tropical system will arrive on
Monday, thickening from south to north Monday afternoon into Monday
night. Despite 850 mb temps near 20 C on Monday, low level
thicknesses are pretty similar to today (Saturday). So went with
solid upper 80s and lower 90s for highs. If any area were to touch
the mid 90s, Metro Louisville is the best candidate.
Cristobal should make the extratropical transition on Tuesday, with
the center of the storm moving north through Missouri. Rich tropical
moisture will continue to be transported northward over the mid-
Mississippi and lower Ohio Valleys. The heaviest rainfall and
greater risk for flash flooding will be off to our west in far
western KY, IL, and MO. But we do see more of an open wave in the
mid levels swing northeast over the region on Tuesday, along with an
increasing southerly LLJ. Expect scattered showers and storms and
breezy conditions, with very efficient rainfall production/high
rainfall rates. Showers and storms may become more numerous at times
west of I-65. Highs will range from the mid 80s to lower 90s.
A large upper trough over the western US early next week eventually
absorbs the remnants of Cristobal over the Upper Midwest by
Wednesday of next week. The system is likely to restrengthen into a
strong mid latitude cyclone over Wisconsin and Lake Superior,
pushing a cold front across the area from west to east on Wednesday.
Therefore, only expect highs in the low to mid 80s Wednesday with
westerly winds bringing in cooler, less humid air heading into
Wednesday night. Medium range ensemble guidance supports upper
troughing/northwest flow aloft and high pressure at the sfc to close
out the work week. Confidence in the details is still fairly low,
but this generally looks cooler and drier at this time. 50s to low
60s for lows and upper 70s to mid 80s for highs are reasonable.
.Aviation...(00Z TAF Issuance)
Issued at 730 PM EDT Sat Jun 6 2020
VFR conditions will prevail at all TAF sites through the forecast
period. Isolated clouds this evening will dissipate after sunset,
with a clear sky overnight and surface winds becoming N to NE around
5 kts. On Sunday, high pressure at the surface will move into the
upper OH Valley resulting in an E to NE surface breeze up to 10 kts
along with a few high level cirrus clouds.
Area Forecast Discussion
National Weather Service Riverton WY
549 PM MDT Sat Jun 6 2020
.SHORT TERM...Rest of Today through Sunday night
Issued at 1153 AM MDT Sat Jun 6 2020
A circulation is seen moving through Utah. This low will be
tracking northeast to central Wyoming by 00Z Sunday. This low and
associated negatively tilted trough is actually circulating within
a larger circulation around a main low off the Pacific Northwest
coast and associated long wave trough. Early morning thunderstorms
have already erupted across southwest Wyoming ahead of the
approaching aforementioned shortwave over the Great Basin.
Pinedale has just recently reported a thunderstorm with heavy rain
at the time of this writing. RKS just reported a thunderstorm
with 66 mph wind gusts. This activity appears to be elevated
convection, embedded within a larger area of stratiform rainfall
according to area web cams and satl loops, given the synoptic
scale dynamics associated with this weather feature. Left-front
quad dynamics associated with the small jet streak tied within
this shortwave, along with QG forcing, are the main forcing
mechanisms. As this large area of clouds and showers shifts
northeast to central Wyoming, central Wyoming should experience a
delay in sfc heating and a weakening in surface based convection
through midday. Meanwhile, our east and northeast zones,
including Natrona and Johnson counties, should get a head start
on the convection around midday. SPC has placed central and
eastern Sweetwater County, southeast Fremont, and the southeast
2/3 of Natrona County in a slight risk of severe weather for
today. The rest of the entire CWA is in a marginal risk. The
models appear to give our southeast zones the greatest potential
for heavy precip today with 3 hourly half inch increments of
precip. PW values are roughly an inch across the east half of the
CWA today, which is down from an inch and a quarter from earlier
runs. Lifted indices are progged to be between -3.5 to -4 in the
far west today and in the northeast zones. CAPE will be up to
1400 J/KG in many portions of the CWA. The long and short of it
is, we could see significant convective activity all around our
CWA today at some point, with perhaps the weakest convection
right in the middle of our CWA in places like the Wind River
Basin. The timing for convection inhibiting cloudiness will have
to be closely tracked today. One could argue the HRRR indicates 4
waves of convection tracking from the southwest to northeast
today, with each one weakening as it encounters the more stable
air over central Wyoming. The main defining feature with today`s
convective cells should be very strong winds, as we have already
seen at RKS, given the 60 knot winds progged at 700mb this
afternoon and evening. Locally heavy rainfall and some small hail
with a few cells are also expected.
Tonight, the cold front associated with this initial shortwave
will filter in the first of the cold air from the west. Numerous
showers will continue tonight. After the first shortwave exits
northeast, showers will begin to mainly focus over western Wyoming
ahead of the next main Pacific Northwest low. As the cooler air
begins to filter in behind the first shortwave, snow levels will
descend down to 8500 feet in the west tonight.
On Sunday, the left-front quad of the main jet streak will
encourage more lift across the area, as well as western Wyoming
getting assistance from QG forcing, as the Pacific Northwest low
opens up as an open wave over the Great Basin, and a new main
circulation reforms to the north over southern Canada. The most
numerous shower activity will take place in western Wyoming, with
scattered showers moving east to areas east of the Divide. There
will be enough instability for some afternoon thunderstorm
activity as well, with very gusty winds given the tight gradient,
and small hail with the lowering freezing level/lowering wet bulb
Then on Sunday night, the reinforcing cold front behind this main
trough will arrive as a classic katafront, with the coldest 700mb
air nosing right into Wyoming behind the Canadian low. Surface 3-
hourly post frontal pressure rises will be on the order of 9-11mb
east of the Divide Sunday evening, so we can expect one more
blast of wind with the frontal passage. Showers will continue,
most numerous in the west, with snow levels descending down to the
valley floors in the Jackson Valley by 12Z Monday. Even areas
east of the Divide could see snow showers as low as 6000 feet,
although shower activity will not be as widespread in these areas.
The Jackson Valley could see less than a half inch of snow by 12Z
Monday, with a few inches in the surrounding western mountains.
As far as river flooding potential is concerned, along with the
heavier precip expected, temperatures will also be falling as
well, so it does not appear that significant rises will occur, given
the ongoing falling stages at most sites
.LONG TERM...Monday through Saturday
Issued at 110 PM MDT Sat Jun 6 2020
The medium-range portion of the forecast begins with northwest flow
across western and central Wyoming. Trough axis will extend
north-south through the forecast area Monday, with plenty of
moisture within the upper flow. Widespread showers will persist
along and west of the Continental Divide. To the east, the Big
Horn Basin, and to a lesser extent the far southwest, will have
the best chance for scattered or better coverage. Expect afternoon
and early evening gusty northwest wind for many areas.
Precipitation and cloud cover will decrease from west to east
Monday night. This could set the stage for freezing or near
freezing temperatures for many lower elevation locations. Better
clearing and higher elevation will almost certainly lead to sub-
freezing lows in the western valleys. The east will be a closer
call and cloud cover is likely to be the primary player. There
could be a few lingering showers over the northwest mountains
Tuesday, otherwise drier conditions and the beginning of a warm
trend are on tap for Tuesday. The gusty northwest afternoon and
evening wind is likely to linger Tuesday.
Flat ridge then begins to build Wednesday. This ridge will gradually
amplify through the remainder of the week, as the next long wave
trough digs along the West Coast. Mid-level temperatures rise to +13
to +16 by Friday and Saturday, so a return to above normal
temperatures is not far off. There could be some late day weak
convection over the northwest by Saturday, but for the most part the
late week pattern will be dry. Southwest Wyoming could see elevated
fire weather concerns by Friday and Saturday, as the southwest
wind cranks up and humidity levels drop back into the teens.
.AVIATION...For the 00Z TAFS through 00Z Monday
West of the Divide...KBPI/KJAC/KPNA/KRKS Terminals
The ongoing showers and storms will continue into the evening, with
a downturn in intensity expected by sunset Saturday. MVFR conditions
will still be prevalent, especially at KJAC. Showers will continue
through around 08Z at KJAC, KBPI and KPNA, before becoming
isolated. KJAC will have the best chance for persistent MVFR
conditions overnight, as early Sunday morning showers are most
likely there. Other terminals should see improving conditions by
12Z, which will linger through the morning. Convection, albeit
not as strong as today, will increase by early afternoon with
occasional MVFR conditions. Gusty southerly wind, especially at
KRKS, will diminish late tonight before increasing toward midday
Sunday. Surface wind will veer to the west and increase later
Sunday afternoon as a cold front pushes east.
East of the Divide...KCOD/KCPR/KLND/KRIW/KWRL Terminals
Expect mainly VFR conditions through the forecast period. Localized
IFR/MVFR conditions are possible, mainly until 03Z, in
association with stronger convection. Southwest surface wind with
gusts 25-35kts will persist into the early evening hours, before
gradually decreasing by 06Z. Outflow wind from daytime convection
will continue to pose a hazard to aviation through 03Z, as gusts
of 45kts or more are possible. The coverage and intensity of
showers and storms will decrease by 06Z, but lingering light
showers will be possible at KCOD and KWRL. Southwest to west wind
will increase at all terminals Sunday afternoon, as a cold front
prepares to cross the forecast area.
Please see the Aviation Weather Center and/or CWSU ZDV and ZLC for
the latest information on icing and turbulence forecasts.
Issued AT 110 PM MDT Sat Jun 6 2020
The first of two storm systems is moving across the forecast area
Saturday afternoon. Showers and thunderstorms will continue through
the evening, before decreasing in coverage and intensity,
especially east of the Continental Divide. However, the showers
will linger across the far west overnight ahead of a second
weather system. This second storm system over the Pacific
Northwest will slowly track east and produce more widespread
showers and storms Sunday and Monday across western Wyoming.
Coverage will be less widespread east of the Divide. Wetting rain
and even mountain snow above 8000 or 9000 feet is likely across
the west and southwest Sunday and Monday. This second system will
push a cold front through western areas late tonight, make little
progress Sunday, and then make its way east through all of the
forecast area late Sunday afternoon and night. The overall trend
will be toward much cooler temperatures for Sunday and Monday,
particularly across the Teton and Yellowstone dispatch areas.
Temperatures will moderate toward midweek with very warm readings
by Friday. Drier weather is anticipated Wednesday through Friday.
Area Forecast Discussion
National Weather Service Blacksburg VA
814 PM EDT Sat Jun 6 2020
A cold front slides across this evening and will be south of the
area late tonight. High pressure builds in with less humid air
for Sunday into Monday. Humidity and rain chances increase with
a front by the middle of next week.
.NEAR TERM /THROUGH SUNDAY/...
As of 800 PM EDT Saturday...
NAM Nest and HRRR so far have hit the nail on the head with the
convection firing off in WV and then traveling SE into our
area. If these CAMs remain true to their word, storms could stay
together until the start to reach the Lynchburg, Roanoke, NRV
before loosing most of their gusto. From there, they will be
more generalized showers. This guidance seems true given the
amount of CAPE sitting out at the moment that needs to be used
up. Because of this, POPs have been changed through the early
evening to bring this line through.
After the storms pass, expect areas that received rain to
develop fog, especially lower valley areas. Sky conditions
quickly recover with much drier air aloft behind these storms.
As of 220 PM EDT Saturday...
Upper ridge will stay situated west of us Sunday, with a trough
offshore. At the surface high pressure builds southward from the
Great Lakes. Expect lower humidity but temps will stay warm in the
upper 70s to lower 80s west, to mid to upper 80s east.
Forecast confidence is low on coverage of storms this evening, as
some models showing a little more over WV/Alleghanys while others
are isolated. Forecast the rest of the period is high.
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
As of 235 PM EDT Saturday...
TS Cristobal will move onshore near the mouth of the Mississippi
Sunday night, heading north-northwest into Arkansas and weakening as
a depression by Monday evening. High pressure will set up from the
Northern Mid-Atlantic southward into the Carolinas, while ridge aloft
strengthens. A surface boundary will be stretched across the Gulf
Coast states, but overall appears dry weather in store into at least
Tuesday morning, then moisture advection increases Tuesday with a
few showers and storms possible in the mountains late in the
afternoon and evening.
Sunday night looks the coolest with lows in the 50s most locations,
except around 60 southeast around Danville/Reidsville, and upper 40s
in the mountain valleys like Burkes Garden.
Staying warm Monday with slight uptick in humidity but still drier
than what we have now. High temps will be mainly in the 80s.
Tuesday looks like Monday on highs, but humidity increases.
Still expect mostly sunny days, Monday-Tuesday barring any mid-high
clouds moving in from Cristobal.
Forecast confidence is high for this forecast period, except low on
the storm chances Tuesday.
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
As of 130 PM EDT Saturday...
An area of high pressure along the east coast will finally move
offshore Wednesday. With high pressure out of the region, a cold
front will move over the area starting Wednesday. If this high
pressure system remains off the coast into Friday, there is a chance
that the front will stall across the area. At this time, models
agree that the front will slowly move over the region and to the
coast Wednesday into Thursday. Behind the front, drier cooler
conditions can be expected with temperatures returning to normal
levels. What will be more noticable will be the drop in humidity as
dew points fall into the 50s.
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
As of 815 PM EDT Saturday...
Convection has fired up along the front that is entering the
area. Models indicate that this line should hold itself
together long enough to bring showers and thunderstorms to LWB,
ROA, LYH, BCB, and possibly BLF. By the time they reach DAN,
they will have substantially weakened. After the rain, its very
likely fog will settle in for the valleys and areas that receive
rain this evening. For now, LWB will be the area that gets the
After sunrise tomorrow, fog mixes out and dry air enters the
area, resulting in VFR conditions settling in for the remainder
of the forecast period
Extended Aviation Discussion...
Dry high pressure will then build across the region with a
period of mainly VFR for Sunday through Tuesday. May see a few
storms arrive Wednesday ahead of a front.