Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 05/04/19
AREA FORECAST DISCUSSION
National Weather Service Albany NY
1014 PM EDT Fri May 3 2019
.SYNOPSIS...
A low pressure system and weak cold front will move across the
region tonight with another round of showers and some isolated
thunderstorms. The cold front will be south of the region
tomorrow with some clouds and a few showers south and east of
the Capital Region. A low pressure system moving across the Mid
Atlantic States along the front Saturday night into Sunday may
bring some rainfall back into the region especially south of the
Interstate 90 corridor. A brief period of mainly dry weather is
expected late Sunday into Monday with weak high pressure
building in.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
As of 1014 PM EDT...Scattered to numerous showers continue to
move across the region late this evening. While the main surface
boundary and weak area of low pressure remain to our west, E-SE
flow has resulted in marine influenced air mass to squelch any
instability. Thunderstorms have been prevalent across
central/northern PA this evening, but lightning has diminished
into southern NY. This activity should weaken as it moves across
our area during the overnight hours. 00Z KALY sounding showed
very little elevated instability, so will remove mention of
isolated thunder. Widespread showers will move back in
associated with the activity in PA, but will decrease in
intensity with only light/moderate rainfall rates around 0.1 to
0.25 inches per hour. Latest few hour runs of the HRRR
indicating slower ending to the showers overnight into early
Saturday morning, so pops were raised during this time. The
occluded front and weak surface low will gradually move through.
Patchy fog may form with the showers in the moist marine air
mass. Low temps will be in the mid and upper 40s north and west
of the Capital District and upper 40s to lower 50s from Albany
south and east.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
Tomorrow...The front settles south of the region near the PA-MD
border and south of Long Island. Weak high pressure will be
ridging in from the Great Lakes Region and southeast Canada.
Some isolated to scattered showers may linger in the morning
south of I-90 close to the I-84 corridor across NW CT, the mid
Hudson Valley and southeast Catskills. The mid and upper level
flow will continue to be zonal across the region. Cloudy or
mostly cloudy conditions will continue through the morning into
the early afternoon.
The best chance of some sun mixing with clouds based on the
deterministic guidance and Ensembles will be across the Upper
Hudson River Valley and the southern Adirondacks, and possibly
briefly into the Capital Region.
Clouds will begin to thicken and lower late in the day
especially across the southern zones with the a wave forming
along the cold front over the OH Valley and Mid Atlantic States.
We blended the latest MAV/MET/ECM guidance for max temps as the
latest MAV guidance seemed too warm, especially if the clouds
hold on with highs in the mid 50s to lower 60s over the higher
terrain and mainly mid and upper 60s in the valleys with a few
70F readings in the mid Hudson Valley.
Saturday night into Sunday...The 12Z GFS/NAM/ECMWF and several
Ensemble members have trended south with the low pressure system
and over running rainfall Saturday night into Sunday. The sfc
low passes over the Chesapeake Bay region staying well south of
Long Island. There is still some uncertainty with the zonal
flow aloft, but we kept a slight to low chance of showers from
the Capital Region/I-90 corridor south, except for portions of
the Mid Hudson Valley/southeast Catskills, and NW CT where we
went with likely/low categorical PoPs especially between 06Z-
12Z SUN...and continuing into the late morning/early pm with a
quarter to half inch of rain. The threat for some light rain
continue during the day Sunday further north, but based on the
latest trends locations from Albany north and west may stay
mainly dry with some clouds lingering north of the wave. A few
showers may linger south and east of the Capital Region in the
afternoon with the mid and upper deformation zone. If the trend
southward continues, then we may lower PoPs further north. Low
temps will be in the 40s to lower 50s with a few upper 30s in
the Adirondack Park. Max temps on Sunday will depend on the
degree of cloudiness and rainfall extent. We leaned closer to
the cooler MET guidance and went with warmer max temps over the
northern zones where some sunshine max mix with clouds. Highs
north of the Capital Region in the Upper Hudson River Valley may
be in the upper 60s with mid 50s to lower/mid 60s expected
across the rest of the region with some locations in the mid
Hudson Valley/NW CT stuck in the upper 50s.
Sunday night into Monday...A drying trend is expected with weak
ridging building in from the OH Valley, and the lower Great
Lakes Region. Some partly cloudy/mostly clear skies are
expected Sunday night with low temps falling into the 40s with
light to calm winds. A prefrontal sfc trough may cause some
clouds to increase Monday well in advance of a cold front. A few
sprinkles or isolated showers may pop-up over the higher
terrain especially north and west of the Tri-Cities though the
synoptic forcing looks weak and our forecast leans closer to the
NAM/ECMWF at this point. Max temps trend closer to normal for
early May with 60s to lower 70s across the forecast area.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
Another wet and cool week looks to be in store for eastern NY and
western New England in the long term forecast. We will be closely
monitoring a stalled stationary boundary and waves of low pressure
riding along it Wednesday through Friday which look to bring us
multiple chances for showers and even periods of rain. Read on for
details.
We start the period Monday night with high pressure in place off the
mid-Atlantic coast as an ana front gradually sinks southward through
Ontario, Canada. We should enjoy mild and dry weather ahead of the
approaching front Monday night into the first half of Tuesday with
southerly flow leading to high temperatures in the upper 60s to even
low-mid-70s for the mid-Hudson Valley and Litchfield County, CT.
However, our approaching ana front will be sliding through our
region Tuesday, especially during the afternoon, from the
Adirondacks through the Capital Region and eventually the mid-Hudson
Valley with surface winds shifting north or northwest on the leading
edge of the showers. This is a classic signature of an ana front and
most areas should experience a noticeable temperature drop as the
showers arrive as a chilly Canadian air mass noses southeast into
the Northeast in its wake. Temperatures Tuesday night should fall
into the 40s to near 50. Mildest
Just how far south and east the ana front penetrates is still
uncertain as the ECMWF shows the front reaching well into the mid-
Atlantic by 12z Wednesday while the GFS and CMC-NH shows it stalling
in southern New England/near NYC. For now, sided closer to the
GFS/CMC-NH but still thinking the cool Canadian high air mass
overspreads most of our region, leaving us with with another stretch
of below normal temperatures Wednesday through Friday. Temperatures
likely do not have much a diurnal change with highs remain in the
50s to near 60 and lows in the upper 40s/low 50s due to persistent
easterly/southeasterly flow maintaining a cool, marine influenced
air mass over eastern NY and western New England.
While there remains uncertainty with the exact placement of our
stalled boundary, the general consensus within the global guidance
supports fast zonal flow persisting for the second half of the week
with embedded weak vort maxes passing within it that should lead to
multiple chances for showers. Thus, we have placed widespread chance
POPs for each period Wednesday to Friday to account for this
pattern. Should the ECMWF be correct with its placement of our
stalled boundary much further south in the mid-Atlantic, Wednesday may
end up being a dry yet cool day.
A stronger low pressure system looks to develop in the Midwest and
push eastward during the Thursday/Friday timeframe which could lead
to more widespread and steadier areas of rainfall. We placed likely
POPs in this window to account for this system. Should any elevated
instability be associated with this low, any areas of convection
could lead to enhanced rainfall amounts.
&&
.AVIATION /02Z SATURDAY THROUGH WEDNESDAY/...
Widespread showers moving across the KALB/KGFL/KPSF corridor
early this evening, while most of the shower activity remains
just north of KPOU. Conditions generally MVFR, although
persistent IFR cigs remain at KPSF. This first batch of showers
should move through by mid evening, although cigs will continue
to gradually lower with the approach of the occluded boundary.
Also, patch fog is expected to develop in the most marine air
mass. Conditions are expected to become widespread IFR by late
this evening into the overnight hours.
Another batch of showers will move across much of the region
overnight as the occluded boundary passes through. A few
rumbles of thunder will be possible but will be too isolated to
mention in TAFs. Conditions should remain IFR through the
overnight hours into early Saturday morning. Showers will end by
Saturday morning, with conditions gradually improving to MVFR.
Skies should remain BKN-OVC Saturday afternoon, but cigs are
expected to improve to VFR levels by around early afternoon.
Winds will be light and variable tonight, becoming north-
northwest around 5 kt on Saturday.
Outlook...
Saturday Night: Low Operational Impact. Slight Chance of SHRA.
Sunday: Low Operational Impact. Slight Chance of RA.
Sunday Night: No Operational Impact. NO SIG WX.
Monday: No Operational Impact. NO SIG WX.
Monday Night: No Operational Impact. NO SIG WX.
Tuesday: Moderate Operational Impact. Chance of SHRA.
Tuesday Night: Moderate Operational Impact. Chance of SHRA.
Wednesday: Moderate Operational Impact. Chance of SHRA.
&&
.FIRE WEATHER...
A weak cold front will move across the region tonight with
another round of showers and some isolated thunderstorms. The
cold front will be south of the region tomorrow with some clouds
and a few showers south and east of the Capital Region. A low
pressure system moving across the Mid Atlantic States along the
front Saturday night into Sunday may bring some rainfall back
into the region especially south of the Interstate 90 corridor.
RH values will increase close to 100 percent tonight in the
rain, and drop to 50 to 65 percent tomorrow afternoon. The RH
values will increase once again to 85 to 100 percent Sunday
morning.
The winds will be light and variable at less than 10 mph
tonight and become north to northeast 5 to 15 mph on Saturday
before becoming light and variable at less than 10 mph on
Saturday night.
&&
.HYDROLOGY...
Showers and isolated thunderstorms will affect our region
late this afternoon into tonight with a weak cold frontal
passage. Rainfall amounts should range between two tenths and
and three quarters of an inch. There could be locally heavier
amounts in any isolated thunderstorms. This rain is not expected
to cause river flooding at this time, but flows will remain
high. Some ponding of water on roadways and poor drainage
flooding of low-lying areas is possible.
Generally dry conditions are expected Saturday except south of
the Capital Region where some very light rain amounts are
possible. Low pressure tracking south of Long Island Saturday
night through Sunday will bring another chance of rain to our
area especially south of the Interstate 90 corridor in the mid
Hudson Valley, southeast Catskills, and NW CT where a quarter to
half an inch is possible. Within bank rises are possible, but no
flooding is expected.
A brief spell of mainly dry weather is expected Sunday night
into early next week, before wet and unsettled weather returns
late Tuesday through the mid week. Flows will remain high for
early May.
Please visit our Advanced Hydrologic Prediction Service /AHPS/
web page for specific area rivers and lakes observations and
forecasts.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
MA...None.
VT...None.
&&
$$
SYNOPSIS...Wasula
NEAR TERM...JPV/Wasula
SHORT TERM...Wasula
LONG TERM...Speciale
AVIATION...JPV
FIRE WEATHER...NAS/Wasula
HYDROLOGY...NAS/Wasula
Area Forecast Discussion
National Weather Service Boston/Norton MA
1006 PM EDT Fri May 3 2019
.SYNOPSIS...
A wave of low pressure will bring another period of rain later
tonight and Saturday morning, with some improvement Saturday
afternoon. Another low pressure tracking south of New Eng may
result in some showers Sunday but it is likely the steadiest
rain will remain to the south. High pressure brings dry,
seasonal conditions Monday and Tuesday. Another frontal system
may bring more showers at mid week.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
Main change to the forecast this evening was to increase
rainfall chances overnight. Last few runs of the HRRR and time-
lagged ensemble HRRR seemed to have a decent handle on timing
and location of showers this evening. Relied upon them heavily
to update timing of rainfall.
Only real threat of thunderstorms overnight remained towards
the south coast of RI and MA, where a lone thunderstorm was
already marching east. Not expecting severe weather from this
thunderstorm, as there is simply not enough energy to work with.
This storm was barely capable of producing lightning.
Once the showers presently in our region move off to the east,
watching another batch of widespread showers towards southeast
PA which should arrive in our region late tonight into Saturday
morning. Still thinking the stronger convection will not be as
prevalent in southern New England, but cannot completely dismiss
the idea of an isolated thunderstorm or two.
Minor tweaks to temperatures overnight.
Previous Discussion...
Next mid level shortwave approaches from the Great Lakes late
tonight and the guidance is showing a frontal wave developing
along the mid Atlc late tonight. Deepening moisture and modest
forcing for ascent will result in a renewed area of showers
developing and moving into SNE late tonight and Sat morning. The
showers should be focused more along and south of the Pike and
isold t-storms are possible near the south coast where 200-400
J/kg of MUCAPE indicated.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
Saturday...
While it will be drying from the north Sat, a wet morning is
likely near the south coast into RI and SE MA with improvement
in the afternoon as some breaks of sunshine should develop with
modest mid level drying. Exception will be near the south coast
and especially Cape/Islands where clouds and patchy fog may
persist. While it should be mainly dry into the afternoon, there
is a low risk for a brief shower developing away from the coast
as models generate weak instability. Light easterly flow will
hold temps in the 50s along the E coast of MA, but temps should
recover into the 60s away from the coast and possibly near 70 in
the CT valley.
Saturday night...
Yet another shortwave will be approaching with the frontal wave
tracking off the mid Atlc coast. Low amplitude shortwave with
flat flow and guidance has trended southward with deeper
moisture. There is uncertainty with how far north showers and
steadier rainfall gets but it is looking more likely that the
steadier and heavier rainfall will remain to the south. Still,
some showers are expected overnight as moisture deepens across
the region. Areas of fog expected again near the south coast.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
Highlights...
* Best chance of showers further south on Sunday
* Dry and seasonable conditions Monday into Tuesday
* Cold front brings showers through late Tuesday/Wed
* Another wet system arrives Thursday or Friday
Sunday...
So one of the biggest adjustments to the forecast is in rainfall
potential during the day on Sunday. While rain is still expected,
trends over the past 24 hours have been toward high pressure to our
north keeping the best forcing and moisture suppressed further
south, and thus the heaviest precip offshore. Guidance still favors
showers, especially south of the MA Pike and best chances during the
morning hours. The second half of the weekend overall looking like
less of a washout, even potential for some sun; better chance of
breaks in the clouds as we go through the day. Onshore winds
continue out of the northeast as we remain on the north side of the
low. Breezy winds expected along the south coast in closer proximity
to the tightest surface pressure gradient. Given less rain/cloud
potential, high temps have been raised a bit into the upper 50s
along the coast, 60s inland.
Monday and Tuesday...
A drier and seasonable few days on tap to start the week. Early
Monday the low exits to the east, replaced by surface/mid level
ridging. A drier column and subsidence under the high brings a mix
of clouds and sun Monday with light winds and highs in the 60s,
warmer in the CT valley. Looks like a perfect day to come check out
the Hurricane Awareness Tour being held by our office at Quonset
State Airport from 2-5 PM!
12Z guidance has come into better agreement on the timing of a
trailing cold front which moves through Tuesday/Tuesday evening.
Remnants of a low over Hudson Bay, it will bring some showers along
and ahead of the front which then hangs up near southern New England
as it becomes parallel to zonal steering flow. Southerly surface
winds bring warmer temps during the day Tuesday, into the 70s for
many in the interior.
Wednesday through Friday...
Models haven`t been handling this progressive spring pattern very
well in the extended, and that becomes more evident as uncertainty
increases by Wednesday. Some question as to how long the overnight
precip lingers into Wednesday as flow remains zonal. With no
substantial shortwaves to get things moving, the front may linger in
the neighborhood keeping rain chances into late Wednesday. For now
have trended drier through the day to reflect a drier ensemble mean
guidance. Tuesday looks like the warmest day of the week. Friday and
beyond we return to a fairly cool patter in the 50s and 60s. Next
wet weather system comes sometime late week.
&&
.AVIATION /02Z SATURDAY THROUGH WEDNESDAY/...
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
Short Term /through Saturday Night/...Moderate confidence.
Tonight...
Widespread IFR/MVFR cigs with areas of LIFR stratus and fog
along the south coast. Another round of showers will mainly move
across northern MA late this evening. Still expecting a round
of showers to move across the region after midnight and be
focused mostly along and south of the Mass Pike with some
scattered showers possible over northern MA. An isolated
thunderstorm or two remains possible along the S coast.
Saturday...
MVFR/IFR in the morning with showers focused near the south
coast, then improving to VFR in the afternoon. A few afternoon
showers may develop in the interior. Areas of stratus and
patchy fog may persist through the day across the Islands and
possibly Cape Cod as well.
Saturday night...
VFR/MVFR cigs trending toward IFR/MVFR with areas of fog along
the south coast. More showers may develop late Sat night,
mainly south of the Pike.
KBOS Terminal...Moderate confidence in TAF, mainly due to timing
of showers.
KBDL Terminal...Moderate confidence in TAF, mainly due to timing
of showers.
Outlook /Sunday through Wednesday/...
Sunday: Mainly VFR, with local IFR possible. Breezy. Chance RA.
Sunday Night through Monday Night: VFR.
Tuesday: VFR. Slight chance SHRA.
Tuesday Night: VFR. Chance SHRA.
Wednesday: Mainly VFR, with local MVFR possible. Slight chance
SHRA.
&&
.MARINE...
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
Short Term /through Saturday Night/...High confidence.
Relatively light winds and seas through Saturday night with
easterly flow. The main impact for mariners will be poor vsbys
at times in areas of fog, especially for south coastal waters.
In addition, showers are likely especially late tonight into
Sat morning and can`t rule out an isolated thunderstorm or two.
More showers are possible Sat night.
Outlook /Sunday through Wednesday/...
Sunday: Winds less than 25 kt. Areas of seas approaching 5 ft.
Slight chance of rain.
Sunday Night through Monday Night: Winds less than 25 kt. Seas
up to 5 ft.
Tuesday: Winds less than 25 kt. Seas up to 5 ft. Slight chance
of rain showers.
Tuesday Night through Wednesday: Winds less than 25 kt. Seas up
to 5 ft. Chance of rain showers.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...None.
&&
$$
SYNOPSIS...KJC/BW
NEAR TERM...Belk/KJC/BW
SHORT TERM...KJC
LONG TERM...BW
AVIATION...Belk/KJC/BW
MARINE...KJC/BW
Area Forecast Discussion
National Weather Service Charleston SC
1015 PM EDT Fri May 3 2019
.SYNOPSIS...
A weak area of low pressure will move northeast of the area
tonight and dissipate through Saturday morning. A cold front
will then push through the region by Sunday night, followed by
drier high pressure into the middle of next week.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
The wave of low pressure is no longer easily identified,
although with the best moisture transport now well offshore and
nocturnal influences in place over land, the risk of any
additional convection is long over with.
Instead the main concern for the rest of the night will be the
continued formation of fog, and also the development and build
down of stratus. The overall potential for fog looks high, but
where the best coverage will be is still somewhat uncertain, as
there remains no consensus between the models. We did start the
development of fog a few hours earlier than previous forecasts,
and based on the RAP and HRRR condensation pressure deficits, we
have included mention of dense fog and a possible Dense Fog
Advisory in the Hazardous Weather Outlook.
It`ll certainly be a warm and humid night, with temps holding
above 70F for most places through 1 or 2 AM, while actual lows
will barely reach 65-70F.
Previous discussion...
The wave of low pressure is seen in surface observations
across southern Georgia, and this feature will continue progress
slowly northeast and will be near or just northeast of the
Santee River by daybreak. Lingering boundaries still have decent
thermodynamics and moisture to work with the maintain isolated
to scattered showers and a few t-storms through mid evening.
Fog potential still looks good, with RAP and HRRR condensation
pressure deficits favorable for at least patchy dense fog late
tonight. Given the wet grounds, this seems highly plausible and
we certainly could need a Dense Fog Advisory or at least a
Special Weather Statement closer to daybreak, pending the amount
of dense fog that occurs.
Discussion from 409 PM...
This Evening and Tonight: A warm and moist airmass will linger
across the region early, helping produce a few showers and
thunderstorms well inland where previous activity has not worked
over the environment. Convection will remain sub- severe, but
PWATS around 1.75 inches along with the slow movement of
activity could produce brief moderate/heavy downpours for the
next hour or two across inland areas.
A weak wave/low will continue to drift across the area tonight.
Despite some convergence associated with this feature, showers
and/or thunderstorms are expected to rapidly decrease in coverage
late evening into early tonight mainly due to diurnal heat loss.
Once activity diminishes, cloud cover should decrease through
midnight, potentially setting up an environment favorable for fog
late. The combination of limited cloud cover, light winds, wet
grounds from previous rains and sfc dewpts in the upper 60s to
around 70 should favor at least patchy fog across all areas late
tonight. The greatest chance of fog appears to be across inland
areas of Southeast South Carolina where temps become cooler late. In
general, lows should range in the mid/upper 60s away from the coast.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
Saturday and Saturday night: The forecast area will be positioned
within the southwesterly flow aloft ahead of a southern stream
shortwave moving along the Gulf Coast. At the surface, the weak wave
of low pressure will move to the northeast and dissipate, leaving
behind a very summerlike environment for the afternoon. Temperatures
should rise into the upper 80s away from the immediate coast, with
dewpoint values in the upper 60s to low 70s. Models are in pretty
good agreement regarding coverage of showers and thunderstorms, with
the main focus being across our inland zones closer to the Midlands.
This area should see the most instability and best low level
convergence. Soundings show around 25 knots of flow in the lowest 5
or 6 km of the atmosphere, so there could be enough shear to produce
some interesting multi-cell clusters. The location of the strongest
storms will likely be determined by boundary interactions through
the afternoon. We can`t totally rule out one or two strong to
marginally severe storms, but it still looks like the best
environment will be present on Sunday. Rain chances are highest
inland, in the 50-60 percent range and taper into the 20-30 percent
range at the coast. Convection will move further inland and
dissipate through the evening. Then late Saturday night showers and
thunderstorms could approach from the west as along and ahead of a
cold front. Expect a mild night with lows likely not falling below
70 along the coast.
Sunday and Sunday night: The trough axis will pass through and help
push a weak cold front through the forecast area during the day.
Thunderstorm coverage should increase from the west in the morning
and peak in the afternoon. Model agreement is good, so rain chances
have been increased into the 60 percent range. The dynamics are much
improved on Sunday, as model soundings show the mid-level flow
increasing into the 50 knot range. This should yield deep layer
shear values on the order of 35-40 knots. Instability is more of a
question mark. The GFS shows CAPE in the 1000-1500 J/kg while the
NAM is a bit higher. This combination of shear and instability make
the Sunday severe threat a bit more interesting. As such, we remain
in a Marginal Risk area from SPC in the day 3 severe weather
outlook. Highs should top out in the mid 80s, but it wouldn`t take
much sun to rise into the upper 80s. Overnight the front will move
to the coast. Could still see some isolated showers or
thunderstorms, but rain chances are much lower and the severe threat
diminished.
Monday: The front will move offshore, and zonal flow will prevail
through the day. The day will be very summerlike with highs in the
mid to upper 80s in a very weakly forced environment. Diurnal
heating should be enough to kick off at least isolated convection.
Added a 20 percent chance of thunderstorms to the forecast. The
larger scale flow will be northerly, and the development of the
afternoon sea breeze should provide enough convergence to initiate
convection. There is a bit more mid/upper level dry air so DCAPE
values are higher than previous days. Could see one or two strong to
marginally severe thunderstorms.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
Moderate to high confidence this period. Mainly dry high pressure
should prevail into mid week before rain chances likely increase
ahead of another cold front. The main question at this point is how
quickly this occurs, possibly as early as Wednesday. Either way it
looks unsettled through the rest of the period with the front likely
still west of the area. Temperatures will cool a bit mid week
before increasing again, but likely staying above normal through the
period.
&&
.AVIATION /02Z SATURDAY THROUGH WEDNESDAY/...
While there could be a few brief episodes of MVFR weather early
tonight, the better chance for flight restrictions will occur
after 07-08Z. This will be as a result of low stratus and fog
developing due to light winds, wet grounds and near 100%
relative humidity. We anticipate at least low-end MVFR, if not
IFR/LIFR, before VFR returns by about 1330Z and continues into
the early afternoon, before scattered showers/t-storms develop
across the area. Until trends are better defined we won`t show
anything more than VCTS after 18-19Z, but periodic flight
restrictions are possible in any convection moves over the
terminals.
Extended Aviation Outlook: Fog and/or low clouds could impact both
CHS and SAV each morning through the weekend. However, greater
chances of flight restrictions are possible with showers and/or
thunderstorms Saturday and especially Sunday as a cold front nears
the area. VFR conditions should prevail at both terminals by
Monday.
&&
.MARINE...
Overnight: The center of weak low pressure will track across
the coastal waters with little to no convective activity as it
shifts off the northeast. Other than a wind shift from east-
southeast to southwest after midnight, conditions will remain
fairly quiet over all coastal waters. In general, wind speeds
will remain at or below 10-15 kt while seas range between 2-4
ft. We did add mention of patchy fog in Charleston Harbor after
4 or 5 am, with some of the fog to slide into the nearby
Atlantic waters as the late night land breeze develops. There
certainly could be a need for a Dense Fog Advisory into Saturday
morning.
Saturday through Wednesday: The local waters will be situated
between high pressure to the east and an inland cold front Saturday,
driving south to southwesterly flow. Wind speeds should top out
around 15 knots in the afternoon. On Sunday the gradient will be
tighter as the front moves closer, and speeds will be a bit higher
topping out in the 15-20 knot range. Monday winds look much calmer
behind the departing cold front, but then increase modestly Monday
night through Wednesday in onshore flow. Seas should generally fall
into the 2-4 ft range through the period.
Rip Currents: A Moderate Risk of Rip Currents continues through
Saturday.
&&
.CLIMATE...
Record high min temps for May 4:
KCHS: 70/1990
KCXM: 73/last set in 1990
KSAV: 70/last set in 1984
Record high min temps for May 5:
KCHS: 70/last set in 1996
KCXM: 73/last set in 2012
KSAV: 70/last set in 2012
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...None.
&&
$$
NEAR TERM...
SHORT TERM...RJB
LONG TERM...RJB
AVIATION...
MARINE...
CLIMATE...
Area Forecast Discussion
National Weather Service El Paso Tx/Santa Teresa NM
325 PM MDT Fri May 3 2019
.SYNOPSIS...
We will be mostly dry over the next seven days, with just a slight
chance for thunderstorms in the Sacramento Mountains this
weekend. Temperatures this weekend will run a couple of degrees
warmer than Friday`s high temperatures. For the start of next week
we will see breezy to windy conditions in the afternoons and then
we will be a little cooler for the middle of next week.
&&
.DISCUSSION...
We continue to be in a generally quiet weather pattern, today
through the weekend. Some deeper moisture continues to lurk just
to the east of the area and this moisture may bring a slight
chance for thunderstorms to the Sacramento Mountains and eastern
Hudspeth County on Saturday and again on Sunday. But more likely
some moisture from the east will leak into the eastern part of the
area, but things will dry back out before convection can get
going by late afternoon. The only thing we will need to keep an
eye on is the fact that sometimes a line of thunderstorms well to
our east will push a long lived moist outflow boundary back to the
west. This could allow moisture to move further west and give a
better chance of thunderstorms to the area. Earlier runs of the
HRRR model kind of hinted at this, for later tonight, but the
later runs have been weakening this west push, so for now I`ll
keep just a slight chance of thunderstorms in the forecast for the
Sacramento Mountains on Saturday and both the Sacs and eastern
Hudspeth County on Sunday. The rest of us will stay dry and warm
as westerly winds push our high temperatures around 5 degrees
above average, which would allow most lowland locations to flirt
with the 90 degree mark on both Saturday and Sunday.
For Monday our attention will turn out west as the next upper
level storm system begins to move toward the region. On Monday,
the upper level low will still be well to our west, but the
southwest flow out ahead of it will allow some moderately
stronger winds aloft to move across the region, so we will be
breezy to windy on Monday afternoon. Then on Tuesday as the upper
level trough opens up, it will help give us another windy day. We
may approach wind advisory level in western New Mexico. The upper
level trough will pass across the Four Corners region, which
should keep it far enough north to keep the associated rain out
of the area. As the trough swings by it will help usher in some
cooler weather, so our highs for Tuesday through the end of the
week will run a few degrees below average. The rest of next week
looks quiet, as a second, weaker trough passes to our north with
little impact on our weather. Just beyond this forecast period,
both the extended GFS and ECMWF bring rain chances into the
region, but for different reasons. The GFS brings a strong push of
moisture in from the east to fuel some thunderstorms, while the
ECMWF doesn`t have as strong an east push, it does sweep an upper
level trough across New Mexico to generate some thunderstorms.
We`ll have to wait and see which solution is correct or perhaps a
drier solution will win out between the two.
&&
.AVIATION...Valid 04/00Z-05/00Z...
P6SM SKC-SCT250 through period. Winds generally SW to NW
AOB 12KTS but will shift around to the E to SE over eastern
zones during the overnight hours before turning back to the
SW after 15Z.
&&
.FIRE WEATHER...
The weekend will feature warm temperatures with mainly single
digit RH`s all areas except some parts of far eastern zones.
A dryline will move west overnight and push back east
during the daytime hours through Sunday with the westward
push up to near the Rio Grande. Isolated showers and
thunderstorms are possible wherever this dryline is located by
early to mid afternoon which should be east of a line from
Alamogordo to Sierra Blanca. Winds through the weekend
will mainly be under 15 mph.
For early next week, an upper low will be moving out of
southern California and into the Four Corners region.
This system will bring increasing winds and possible
critical conditions with best chance coming on Tuesday
with near critical Monday. As this system lifts out,
temperatures will cool down to near normal for the
remainder of the week with slightly higher relative
humidities, but still likely remaining in the
lower to mid teens for the lowlands.
&&
.PRELIMINARY POINT TEMPS/POPS...
El Paso 59 89 62 91 / 0 0 0 0
Sierra Blanca 53 83 58 86 / 0 0 0 10
Las Cruces 52 87 55 87 / 0 0 0 0
Alamogordo 53 85 57 89 / 0 0 0 0
Cloudcroft 38 64 42 66 / 0 20 0 20
Truth or Consequences 54 87 56 87 / 0 0 0 0
Silver City 49 77 52 79 / 0 0 0 0
Deming 49 87 52 87 / 0 0 0 0
Lordsburg 49 86 52 86 / 0 0 0 0
West El Paso Metro 58 87 62 90 / 0 0 0 0
Dell City 52 84 56 92 / 0 0 0 20
Fort Hancock 56 90 62 94 / 0 0 0 10
Loma Linda 55 83 59 85 / 0 0 0 0
Fabens 57 90 62 92 / 0 0 0 0
Santa Teresa 53 87 57 89 / 0 0 0 0
White Sands HQ 59 86 62 89 / 0 0 0 0
Jornada Range 50 87 54 87 / 0 0 0 0
Hatch 50 87 52 89 / 0 0 0 0
Columbus 54 88 57 89 / 0 0 0 0
Orogrande 53 85 57 89 / 0 0 0 0
Mayhill 43 72 46 76 / 0 20 0 20
Mescalero 42 72 46 76 / 0 20 0 20
Timberon 40 69 44 74 / 0 20 0 20
Winston 40 80 41 81 / 0 0 0 0
Hillsboro 49 85 51 86 / 0 0 0 0
Spaceport 48 86 51 87 / 0 0 0 0
Lake Roberts 39 79 41 80 / 0 0 0 0
Hurley 46 81 49 82 / 0 0 0 0
Cliff 40 85 43 86 / 0 0 0 0
Mule Creek 46 80 49 81 / 0 0 0 0
Faywood 49 81 52 82 / 0 0 0 0
Animas 48 88 52 87 / 0 0 0 0
Hachita 47 87 50 87 / 0 0 0 0
Antelope Wells 49 87 53 87 / 0 0 0 0
Cloverdale 50 82 53 81 / 0 0 0 0
&&
.EPZ WATCHES/WARNINGS/ADVISORIES...
NM...None.
TX...None.
&&
$$
Brice/Grzywacz
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
852 PM CDT Fri May 3 2019
.UPDATE...
Quick Update. The main concern continues to be the line of
thunderstorms from El Indio to Hondo to San Antonio to New
Braunfels, Bastrop, and Giddings. Behind the line light rain
continues. There continues to be many threats with this line mainly
strong gusty winds and heavy rainfall leading to flash flooding. We
have seen numerous reports from Dripping Springs and Austin of
evacuations, water rescues, and low water crossings closed. We
continue to urge people to not travel tonight if they don`t have too.
We have also seen little spin up circulations on the northern end of
the line in Bastrop County headed into Lee County and also in
Guadalupe county. The good news is that the this line will continue
to move off to the east and southeast and should clear our area by
about 3 am. Dry weather is in the forecast for tomorrow and Sunday
before more rain next week! Other than dropping counties from the
Severe Thunderstorm Watch that are now behind the line PoPs have been
adjusted to fit radar trends and hourly grids were also trended.
&&
.PREV DISCUSSION... /ISSUED 646 PM CDT Fri May 3 2019/
AVIATION...
Thunderstorm complex near AUS is expected to begin propagating
towards SAT/SSF by 02Z with heavy rainfall associated with this
complex producing IFR/MVFR visibilities and ceilings through 08Z
before it clears Interstate 35. Stronger cells may be able to produce
wind gusts near 40 knots. Stray TSRA may skirt DRT but will handle
impacts with amendments as confidence was not high enough to maintain
a TEMPO based on latest radar presentation.
Once the line exits to the east with the passage of an associated
mid-level trough axis now over West Central Texas, have trended
ceilings close to HRRR output with VFR ceilings prevailing through
the end of the period. May see a few MVFR ceilings attempt to develop
at all of the terminals closer to sunrise as southerly low level
winds persist behind this system, but veering winds should clear out
any ceilings that develop mid to late morning Saturday. Otherwise,
light and variable winds will become northeasterly 5-10 knots during
the day Saturday for AUS/SAT/SSF and southeast around 10 knots for
DRT.
PREV DISCUSSION... /ISSUED 440 PM CDT Fri May 3 2019/
UPDATE...
Quick update for Severe Thunderstorm Watch 127 that has been issued
for the entire South Central Texas area. Strong to Severe
thunderstorms are already ongoing across the Edwards Plateau in
Northern Val Verde County and across Northern Kendall/SE Gillespie
Counties. This activity will gradually move east and southeast
through the evening and into the overnight hours.
PREV DISCUSSION... /ISSUED 246 PM CDT Fri May 3 2019/
SHORT TERM (Tonight through Saturday Night)...
We`ll take "All Scales of Motion" for $500 today across South
Central Texas. Fortunately, the variety of forcings from local and
low (boundaries) to region-wide and high (shortwave trough and jet
streak exit region) have dissipated into the background regime or are
consistent enough to settle into a climatologically-favorable
morphology for this afternoon through tomorrow morning. The 12Z
NAM/GFS/ECMWF and more recent TTech WRF/HRRR/HREF runs are in general
agreement with that evolution, from isolated to scattered storms
moving from West Texas and Mexico into the Rio Grande Plains this
afternoon, to an eventual merging of cold pools and an MCS rolling
though the southeastern 1/2 of the area. Some supercells are
possible through early evening before the cold pools merge.
The greatest severe threat will be damaging wind, with lesser threat
of large hail and a very small chance for a tornado or two. The
prime severe threat area will be near supercells along the Rio Grande
through about 7-8 pm, then transitioning to along and east of I-35 by
10-11 pm. Of special concern area is along and south of U.S. 90 from
Uvalde to San Antonio to Gonzales, where the models indicate the
highest damaging wind threat. Rainfall amounts will be spotty in the
west, from 1/10 inch up to one inch. Locations in the middle should
see 1/4 to one inch, and locations along and east of I-35 1 to 2
inches. A few spots east of I-35 may see up to 4 inches. Some minor
flash flooding is possible due to the rain/runoff from storms earlier
today, in addition to the storms expected tonight.
The good news is the shortwave trough will move east and a rapid
clearing/drying trend from west to east will occur on Saturday. Rain
should be over by midday except for all but the far eastern coastal
plains, and rain should end there by mid-afternoon. Some fog is
likely late Saturday night along and east of I-35, but that will be
addressed by later forecasts when the clearing trend and near-ground
wetness after the rain are more evident.
LONG TERM (Sunday through Friday)...
Sunday is the day for outdoor activity for the next week, with low-
amplitude ridging is over the area. Temperatures will be seasonal and
relative humidity fairly low after daytime heating dissipates
morning fog.
The longwave pattern will become increasingly favorable for severe
storms and heavy rain as next week progresses, with a large and
digging western U.S. trough, and a strengthening Jet Stream across
northern Mexico and into Texas. Shortwave troughs will eject out of
the longwave trough every 24-36 hours to provide the primary lift. At
this time, Monday, Wednesday, and Friday appear to be the days with
the best chances for rain. The chances for severe storms will
increase for Wednesday and Friday as the shortwave troughs are deeper
and the boundary layer has more time to moisten and increase
instability. Friday is of the highest concern, as a cold front
appears to stall from west to east across our area. Diffluent
1000-500 mb thickness over our area points to slow-moving, stalling,
or possibly even back-building convection. Combined with echo
training along the front, that is a recipe for very heavy rain and
significant flash and river flooding. While at this forecast range
details are variable and fuzzy, pay attention to the how the forecast
evolves through the week.
&&
.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry 80 64 80 62 83 / 50 70 20 0 0
Austin Bergstrom Intl Airport 81 62 80 61 83 / 50 70 20 0 0
New Braunfels Muni Airport 81 64 80 61 83 / 40 70 20 0 0
Burnet Muni Airport 77 61 78 60 81 / 60 60 10 0 0
Del Rio Intl Airport 76 64 85 65 85 / 70 40 10 0 -
Georgetown Muni Airport 77 63 79 60 83 / 60 70 20 0 0
Hondo Muni Airport 81 64 83 62 85 / 40 60 10 0 0
San Marcos Muni Airport 82 64 80 61 83 / 50 70 20 0 0
La Grange - Fayette Regional 80 66 82 63 85 / 60 80 30 0 0
San Antonio Intl Airport 79 64 81 63 84 / 40 70 10 0 0
Stinson Muni Airport 82 66 81 63 84 / 40 80 10 0 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Aviation...Huffman
Short-Term/Long-Term...Treadway
Public Service/Data Collection...33
Area Forecast Discussion
National Weather Service Grand Forks ND
952 PM CDT Fri May 3 2019
.UPDATE...
Issued at 952 PM CDT Fri May 3 2019
Additional adjustments made to sky grids in the near term to
reflect clearing and dissipation of showers/thunderstorms in our
east. Showers over north central ND still expected to move
eastward generally along International Border with very light
amounts. Very sharp cutoff in surface/BL Tds behind frontal
passage this evening, with fog developing over parts of west
central MN in warm/moist sector but clearing and Tds in the teens
in ND. This deep dry air will limit potential for measurable
precip further south tonight.
Better forcing eventually arrives Saturday as a second stronger
cold front pushes through our CWA. A period of isolated to
scattered light showers is advertised by consensus of higher
resolution guidance (though this could be oversold in coverage of
measurable). Depending on mixing behind this front we could see a
period of gusty winds as well, but mixing heights at time of post
frontal LLJ are still not lining up enough to increase winds too
much.
UPDATE Issued at 701 PM CDT Fri May 3 2019
Isolated thunderstorms redeveloped/intensified along prefrontal
surface trough in far northwest MN. RAP analysis indicated MU CAPE
(dominated by surface parcels) in the 500 J/KG range. Freezing
heights in the 5000 FT AGL range (-20C heights in the 14KFT range)
have supported better hail potential despite limited updraft
heights. With loss of daytime heating, weaken of updrafts has been
observed. In the meantime strong low level vorticity in proximity
to pre-frontal trough/wind shift line, combined with steep low
level lapse rates has supported funnel cloud development with
updrafts that develop. Impacts from these are limited, but will
remain possible through sunset when loss of daytime
heating/favorable low level lapse rates will end the threat.
Adjustments made to account for lingering thunderstorm/shower
activity early this evening and associated sky cover. Also added
patchy fog to our southeast counties based on consensus of latest
short range guidance.
&&
.SHORT TERM...(This evening through Saturday night)
Issued at 307 PM CDT Fri May 3 2019
Challenge for the short term period is convective activity this
evening which includes thunder potential and end timing. There is
a narrow ribbon of instability with up to 500J/kg of CAPE that
has developed within the WAA band of precip and SFC front with
westerly wind push. Will see the activity continue to push to the
east late this afternoon into the early evening. Precipitation is
expected to be east of the area by 7 to 8 pm.
Overnight tonight cold front is expected to drift south and bring
some slight shower chances to the northern half of the FA. Then
tomorrow the slight shower chances slide into the central and
southern portions of the area. Temps remain on the cool side of
normal with highs in the 50s.
.LONG TERM...(Sunday through Friday)
Issued at 307 PM CDT Fri May 3 2019
NW flow aloft gradually becomes more zonal as an upper low moves
from wrn Ontario into Hudson bay. The zonal pattern persists
through Mon night, when a short wave moves across the area. The
wave could bring thunder to the far south with a rain-snow mix or
snow late Mon evening. The upper level then transitions to a split-
flow pattern with the northern stream over the northern tier keeping
rather cool air in place, with daytime highs generally in the mid to
upper 50s for the next work week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 701 PM CDT Fri May 3 2019
Isolated showers/thunderstorms in northwest MN should move east
and eventually dissipate after sunset this evening. Additional
showers may move into the region from northcentral ND, but
coverage is still a question (better chances near the
International Border). VFR should prevail, unless a terminal is
impacted by shower/thunderstorm. There is potential for fog to
develop in west central MN late tonight, but confidence was too
low to introduce to KBJI at this time.
&&
.HYDROLOGY...
Issued at 306 PM CDT Fri May 3 2019
Moderate flooding continues along the mainstem of the Red River from
Oslo to the Canadian border. The Red River at Fargo/Moorhead and
Grand Forks/East Grand Forks remains in minor flooding.
Lastly, the Red River at Wahpeton/Breckenridge has fallen below
flood stage and the warning has been cancelled. Although there will
be a few showers and storms this afternoon, there will be little if
any impact on the river system.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...None.
MN...None.
River point flood warnings continue across portions of
the region. Refer to the latest flood warnings and statements for
detailed information on specific locations.
&&
$$
UPDATE...DJR
SHORT TERM...JK
LONG TERM...Speicher
AVIATION...DJR
HYDROLOGY...Speicher
Area Forecast Discussion
National Weather Service Hastings NE
628 PM CDT Fri May 3 2019
.SHORT TERM...(This evening through Saturday night)
Issued at 447 PM CDT Fri May 3 2019
Focusing on only the first 36 hours (three forecast periods) in
this section, the main issues include: 1) Potential for a few
marginally-strong storms through this evening with small
hail/gusty wind potential (mainly in the northwest half of our
coverage area/CWA)...2) Could some fog develop into mainly our
southeast zones late tonight/Sat AM?...3) A somewhat better chance
for a few strong to severe thunderstorms Saturday afternoon-
evening as instability levels continue to creep upward (most of
our CWA is now in a Marginal Risk from SPC on the Day 2 outlook).
Otherwise, Saturday still looks to be our first day with
widespread highs into the 70s in over a week.
Taking a look at the current/recent weather scene as of 4 PM:
Again, no big surprises today at all. Following a round of
overnight rain across mainly our southern half (that dropped
several tenths of an inch in some spots), a varied mix of
clouds/sun and mainly dry conditions have prevailed through most
of the day. However, as expected, a narrow/broken line of showers
and fairly weak thunderstorms has in fact developed with the
heating of the afternoon and along a low-level convergence zone
along a surface trough in our far west-northwest CWA. Mesoscale
analysis suggests up to around 500 J/kg of surface-based CAPE in
the presence of at least 30-35KT of deep-layer shear, so this
could be just enough to spark some small hail/gusty winds as these
storms progress east-southeast late this afternoon into this
evening, but severe storms appear rather unlikely. In other
departments, fairly light southerly breezes prevail across most of
the CWA ahead of the aforementioned surface trough axis.
Temperatures are on track to top out in the 65-68 range most areas
(roughly 3-4 degrees warmer than yesterday). In the big picture of
the mid-upper levels, water vapor satellite and short-term model
data continue to show a broad/large-scale trough extended over
much of the CONUS, with various/mainly weak embedded disturbances
within it (including some weak ripples aiding our ongoing
convection).
Now looking ahead forecast-wise through these next 3 night/day
periods...
This evening/tonight:
See preceding paragraph on reasoning behind why a few marginally-
strong storms cannot be ruled out, mainly northwest of a
Fullerton-Kearney-Phillipsburg line. Based on the HRRR (which has
performed very well so far with the ongoing activity), convection
should gradually decrease in coverage/organization/intensity as it
enters the southeast half of our CWA and diurnal heating starts to
fade. That being said, have at least a slight/20 percent chance of
showers/isolated storms extended into all but our far southeast
zones this evening. While a few showers could linger until
roughly midnight (especially in our northeast), the vast majority
of the CWA should see a dry overnight period, marked by mostly
clear to partly cloudy skies, and rather light breezes (largely
around 5 MPH or less). That being said, there are subtle hints in
a few models (especially GFS) that the very late night hours could
feature a few developing sprinkles/light showers mainly in our
southwest, so have added this small chance to the forecast.
Otherwise, while not expecting widespread fog issues, have also
added a generic "patchy fog" mention to some of our southeast
counties, as both the HRRR/RAP visibility progs suggest this area
would be most favored for possible fog development. Low temps
tonight were actually nudged up 2-3 degrees, with most of the CWA
expected to hold up well into the mid-40s (except near-40 far
north around Ord area).
Saturday daytime:
Confidence has decreased a bit versus 24 hours ago regarding
"exactly" how the precipitation/thunderstorm potential will play
out. While most of the CWA should be dry most of the day, there
are now at least small chances for spotty rain showers during the
morning hours especially in our western half, along with
suggestions from several models that especially the northwest half
of the CWA could see at least isolated (perhaps scattered?)
thunderstorm development during the mid-late afternoon. As a
result, afternoon rain chances (PoPs) have been increased/expanded
in area a bit versus previous forecasts, but again, most areas
will probably get through the late afternoon hours dry. If any
storms do pop with the heating of the afternoon and with the aid
of a weak passing upper wave, agree with the SPC Day 2 that a
Marginal Risk of severe is justified, as mixed-layer CAPE around
1000 J/kg is likely (roughly double of today), along with modest
deep-layer shear around 30KT. Certainly a few marginally-severe
storms appear possible in this environment. Otherwise, assuming
that possible early-day showers don`t disrupt the low-level wind
fields appreciably, it looks to be a touch breezy from the south
much of the day, sustained 10-15 MPH/gusts to around 20 MPH.
Temperature-wise, made very little change to high temps, aiming
most areas into the 72-75 range, but if rain holds off well into
the afternoon and skies remain mostly sunny, could easily see
things climbing a bit warmer than advertised.
Saturday evening-night:
Don`t have a great feel for the details of storm coverage, but
anything that develops late afternoon will easily continue into
the evening, and in addition, the presence of a low level jet
overnight could result in new/additional thunderstorm development
even late into the night, at least on an isolated/random basis.
Not expecting much of a severe weather risk after midnight,
however. Again, not expected widespread coverage of storms/heavy
rain, and thus why Pops are mainly just around 30 percent through
the night. with continued southerly breezes, our trend of
increasingly-warmer nights should continue, and have most of the
CWA dropping no lower than upper 40s-low 50s.
.LONG TERM...(Sunday daytime through Friday)
Issued at 447 PM CDT Fri May 3 2019
General overview of this 6-day period:
Just not enough time today to go into much detail, but here are
the main takeaway points:
1) A very active weather pattern with SEVERAL chances for rain
continues through Wednesday night, with the overall-best chances
for more widespread rains focused during the Mon night-Wed night
time frame as a larger-scale shortwave trough gradually approaches
and passes through the Central Plains from the southwest. Very
generally speaking, most of the CWA is expected to average
1.50-2.50" of total rainfall through the next week (per latest WPC
7-day QPF). Of course, with thunderstorms involved, some areas
will surely see localized higher amounts. So whether you want it
or not, plan on receiving a decent amount of rain at some point
through the early-middle part of next week.
2) Severe thunderstorm potential: Along with Saturday (as
described above), both Sunday and Monday carry potential for at
least limited severe thunderstorm development, as they will be
the overall-warmest and most unstable days of the next week.
Although too soon to talk details, both the GFS/ECMWF suggest that
CAPE of 1000-2000J/kg are likely in parts of the CWA on both of
these day, and thus a severe risk could develop, especially during
the favored late afternoon-evening hours. One limiting factor to a
more widespread threat will be dewpoints probably "only" in the
50s, thus keeping "extreme instability" at bay, along with the
fact that upper forcing appears fairly weak/disorganized, although
a decent cold front could provide plenty of low-level forcing for
Monday. Overall, agree with the current Day 3 Marginal Risk from
SPC for Sunday, and fully expect the new Day 3 that comes out
tonight to reintroduce at least a Marginal Risk to Monday
(somewhat oddly to this forecaster, severe probabilities were not
maintained for Monday on last night`s Day 4 outlook).
3) Temperature-wise, no major changes versus previous forecast,
although especially Monday continues trending a bit cooler (4-7
degrees cooler than previous forecast), due largely to a bit
faster invasion of the aforementioned cold front. Thus, it now
appears that especially for Nebraska zones, Sunday is probably the
overall-warmest day (mid 70s), with Monday then featuring a bit
more of a gradient from only mid 60s far north to around 80 far
south. For sure, Tues-Wed will be noticeably cooler with highs
mainly in the 50s to low 60s, due in part to more widespread
clouds and rain (and thus less potential for severe storms.
Thursday also looks rather cool (highs in the 50s to near 60)
before Friday nudged back up into the 60s.
For those looking for truly dry days, very early indications
suggest that Thursday should be mostly dry (despite some "iffy"
rain chances in parts of the CWA in the latest forecast), with
Friday looking like a better bet for dry weather. However, with
this being a full week out, confidence is not overly-high.
&&
.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Saturday)
Issued at 616 PM CDT Fri May 3 2019
-SHRA should end shortly at GRI. VFR is forecast with a little bit
of BR in the morning for GRI. The winds will be light overnight
and with this evenings rain, figure GRI could see a little patchy
light fog tomorrow at sunrise. Winds will be variable overnight
and will become southerly as the weak high pressure over the
region shifts east. Near the end of the TAFs denoted some VCTS as
daytime heating along with a mid-level trough will move through
the area tomorrow afternoon which may fire a few thunderstorms
near the TAF sites.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...None.
KS...None.
&&
$$
SHORT TERM...Pfannkuch
LONG TERM...Pfannkuch
AVIATION...Beda
Area Forecast Discussion
National Weather Service Houston/Galveston TX
804 PM CDT Fri May 3 2019
.UPDATE...
Our brief respite between convective systems is about to end as
large MCS/MCC is evolving over central TX early this evening.
Storms are beginning to get more organized into a linear structure
with pronounced sely motion getting established. Expect this MCS
to track quickly southeast through the rest of the night, with
ewd development into sern TX as main line surges towards the
coast.
Have cleaned up forecast in wake of earlier storms, and tried to
time arrival of next round of tstms starting far nw counties
8-9pm and perhaps moving across Houston metro around 12a-3a
window when it will also be reaching the middle TX coast. Intense
rainfall rates can be expected with these storms, likely causing
flash flooding especially over areas already drenched over the
past couple of days. Will keep Flash Flood Watch in place to cover
those locations, mostly along and north of I-10. However, these
storms will be capable of localized flooding even outside the
watch. Fortunately the complex/line will be moving quickly and
should not linger over any one location. Although, this will
increase the potential for strong to damaging winds as the line
blows through. Large hail and an isolated tornado or two are also
in play through the night with the stronger cores.
In wake of this impluse, could still see lingering tstms through
the morning, but then generally expect most of the rain/tstms to
pull away as mid/upper level impulse continues moving ewd tomorrow.
Evans
&&
.DISCUSSION...
&&
.PREV DISCUSSION... /ISSUED 645 PM CDT Fri May 3 2019/
AVIATION...
VFR conditions this evening will deteriorate once again overnight.
Per hires guidance, ongoing shra tstms in the Hill Country should
evolve into a se/ese moving squall line across the region
overnight. There are various timing differences and details
between models so, in general, went with a compromise between the
HRRR and Texas Tech WRF in regards to timing advertised in the
00Z set of TAFS. Expect amendments thru the night as trends are
established. Most of the activity should be well east of the terminals
before sunrise followed by a break in the action. Will probably
need to throw mention of precip back into the TAFs at some point
during the day Sat as the atmos recovers and daytime heating
performs its magic. 47
&&
.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 66 82 63 85 65 / 90 50 0 0 0
Houston (IAH) 69 83 66 86 67 / 90 70 0 0 0
Galveston (GLS) 72 79 72 81 73 / 90 80 0 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...Flash Flood Watch through Saturday afternoon for the following
zones: Austin...Brazos...Burleson...Coastal Harris...
Colorado...Grimes...Houston...Inland Harris...Madison...
Montgomery...Northern Liberty...Polk...San Jacinto...
Southern Liberty...Trinity...Walker...Waller...Washington.
GM...NONE.
&&
$$
Area Forecast Discussion
National Weather Service Jacksonville FL
921 PM EDT Fri May 3 2019
.UPDATE...Isolated showers and storms continue across Ne Fl
due to a trough of low pressure interacting with a moist and
unstable airmass over the area (SB Cape on 00z Jax sounding
3661J). This activity will gradually wane next several hours
due to loss of daytime heating and trough begins to lift out.
As the trough lifts out overnite deep layer ridging and dry air
aloft will begin to move in and coupled with adequate low level
moisture could lead to areas of low clouds and fog. High-res HRRR
continues to show mainly low clouds (with patches of fog) developing
near I-75 corridor and moving into much of the area early Sat am.
Any patchy fog and low clouds should lift by mid morning.
&&
.AVIATION...Isolated storms will continue to wane the next few
hours but have VCTS at GNV and VQQ til around 03Z. High-res HRRR
continues to indicate low clouds forming towards the gulf coast
and spreading east. Have carried previous fcst of IFR at GNV aft
08Z and MVFR at JAX... VQQ...and CRG aft 09Z-10Z. Conditions
improve to VFR by 14Z-15Z Sat.
&&
.MARINE...Weak low pressure will move north of the waters tonight.
A few isolated storms possible tonight.
Rip Currents: Moderate risk.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 67 88 68 83 / 0 0 30 60
SSI 70 85 70 83 / 0 0 10 50
JAX 68 90 69 87 / 20 0 10 50
SGJ 67 87 69 85 / 20 0 0 50
GNV 66 88 68 86 / 20 0 10 50
OCF 66 89 68 88 / 20 0 10 40
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AM...None.
&&
$$
PP/KB
Area Forecast Discussion
National Weather Service North Platte NE
727 PM CDT Fri May 3 2019
.SHORT TERM...(This evening through Saturday night)
Issued at 317 PM CDT Fri May 3 2019
Modest severe weather conditions are beginning to take shape
across wrn and ncntl Nebraska Saturday with winds aloft increasing
to around 35 Kts and MLCAPE around 2000 J/KG. This places the
Bulk Richardson number between 25 and 50. The uncertainty in the
forecast lies in how far west the return moisture can progress in
the wake of the cold front moving through today. The forecast
follows the short range blend which suggests isolated to scattered
thunderstorm chances across swrn and ncntl Nebraska Saturday.
For late this afternoon and tonight, just ordinary thunderstorms
are expected given the weak winds aloft and lack of instability. The
HRRR shows this activity developing from around Stockville north
through Broken Bow and O`Neill.
The situation Saturday looks toward the Cheyenne divide, ncntl
Nebraska and southwest Nebraska for storm development along a weak
frontal boundary.
.LONG TERM...(Sunday through Friday)
Issued at 317 PM CDT Fri May 3 2019
Thunderstorms may develop off the Black Hills Sunday with northwest
flow aloft. If the storms develop diurnally across the Black Hills,
around 18z-21z, then they would reach ncntl Nebraska early
evening. These storms will be developing in a post-frontal
environment with strong shear but limited instability. Thus,
ordinary storm development would appear to be the operative mode.
The forecast Monday is more uncertain. The NAM and GFS, place wrn
and ncntl Nebraska in cool stable air; a post frontal environment.
This will have a large impact on temperatures from the previous
forecast which was advertising Monday as the warmest of the 7 day
forecast.
Cool air will remain locked into wrn and ncntl Nebraska Tuesday
through Friday. This is the result of a blocking ridge in the north
Pacific and downstream, a long wave trof across the Rockies. The
forecast is fairly consistent predicting below normal temperatures
for a few days. The long wave trof will be a source of upper level
support for rain chances and even snow with the cold model, the ECM,
suggesting snow at times Wednesday through Friday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 723 PM CDT Fri May 3 2019
Skies will be mostly clear tonight behind a departing weak cold
front. VFR conditions will prevail tonight through Saturday.
Isolated to scattered thunderstorms could develop later Saturday
afternoon into Saturday evening. Coverage will be limited and
will not introduce into area TAFs at this time.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...CDC
LONG TERM...CDC
AVIATION...Taylor
Area Forecast Discussion
National Weather Service Memphis TN
744 PM CDT Fri May 3 2019
.UPDATE...
Radar indicates a few showers and thunderstorms west of the region
this hour. The latest high res guidance continues to indicate much
of this weakening before it reaches the area, with the greatest
chance for showers and storms areawide being after midnight.
Current forecast is on track. Sending new zones only to update
timing wording.
ZDM
&&
.PREV DISCUSSION... /issued 253 PM CDT Fri May 3 2019/
Short term...area of light showers has been able to maintain
itself this afternoon. Not sure if they are linked to any embedded
shortwave trough or just the overall continued southwest upper
flow. Temperatures though have been cool enough...mainly in the
low and mid 70s so the instability is struggling to reach a
1000j/kg CAPE. From this thunder and lightning should remain
isolated at best through this evening.
Tonight and tomorrow...main trough axis across New Mexico will
swing through the Ozarks and Midsouth over the next 30 hours.
Models remain in good agreement that thunderstorm coverage should
ramp up quickly after midnight...and last through early afternoon
Saturday...with brief periods of heavier rainfall and a low end
threat for a strong or severe storm. Best threat for isolated
severe storm will be south of I-40 where shear will be stronger.
Then during the mid to late afternoon hours coverage should start
to ramp down from west to east as an associated weak cold front
slips through the region. By sunset only a few stray showers on
the front may still be occurring in the east. Additional rainfall
amounts will range from three-quarters to an inch and a half.
Clouds and precipitation will keep tomorrow`s highs below normal.
One would expect some clearing tomorrow night behind the
front...but it appears the weak boundary layer flow may quickly
allow for stratus...fog and even some patchy drizzle to form. Lows
will fall into the mid 50s to low 60s.
Sunday and Monday...surface high pressure will slowly slide from
the Ohio River Valley to the Tennessee River Valley this period.
Clouds should slowly erode Sunday morning with a light north
breeze keeping highs in the 70s. Warmer temperatures are
anticipated Monday as winds turn back from the south. High level
clouds will skirt across the northern counties Monday night as
convection fires on a warm front in the Lower Missouri Valley.
Tuesday through Friday...long term solutions showing another
repeating wet pattern setting up across the Southern Plains and
Midsouth. Don`t feel each day will be a complete washout as the
GFS is indicating...but overall rainfall amounts of 2-3 inches
are likely this period. Severe weather could also be a factor like
it was this past week...but pinpointing which day is questionable
as upstream MCS activity in the ARKLATEX will have mesoscale
affects on our area. Temperatures will start off above normal
Tuesday...but lower to seasonal averages by Friday.
JAB
&&
.AVIATION...
00Z TAF cycle
Variable conditions are expected over the upcoming TAF cycle
featuring periods of showers and thunderstorms. Made an attempt at
timing the initial round of storms based mainly on HRRR guidance,
but also extrapolation from the development near and west of
Little Rock. Amendments will likely be necessary, especially if
additional storms develop ahead of stuff moving across central
Arkansas. Winds will be light and variable overnight with mainly
MVFR cigs as precipitation begins. Precipitation will linger
across much of the the region tomorrow, but should not be
continuous. Will maintain VCSH at MEM, MKL and TUP through the
with precip ending at JBR after 19z. Winds will shift Northwest
tomorrow, but remain fairly light.
30
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...None.
MO...None.
MS...None.
TN...None.
&&
$$
Area Forecast Discussion
National Weather Service Paducah KY
855 PM CDT Fri May 3 2019
.UPDATE...
Issued at 855 PM CDT Fri May 3 2019
Updated the forecast to speed up the arrival of and eastward
progression of showers and a few thunderstorms across the region
tonight. A fairly solid line of convection will reach Carter and
Ripley counties by 10 PM, and HRRR data pushes it eastward even
to the Evansville Tri State by morning. Thunder will be most
likely as the line arrives, and should become more sparse as it
pushes east of the Mississippi.
UPDATE Issued at 638 PM CDT Fri May 3 2019
The AVIATION section has been updated for the 00Z TAF issuance.
&&
.SHORT TERM...(Tonight through Saturday night)
Issued at 250 PM CDT Fri May 3 2019
Next upper level system headed our way will bring the region more
rain and possibly a few thunderstorms tonight, especially later in
the night, through Saturday. A surface boundary and weak wave
along it will remain to our south. Once the system passes to our
east, rain chances will end from west to east Saturday afternoon
and evening. Used cooler raw model output temperatures as a guide
Saturday given the clouds and rain. Overall QPF from anywhere from
1/3-3/4", higher amounts south. Considerable clouds through
Saturday, decreasing Saturday night.
.LONG TERM...(Sunday through Friday)
Issued at 250 PM CDT Fri May 3 2019
Average confidence in the extended with synoptic scenarios. There
continues to be timing issues with the start and end of
precipitation next week.
Will likely have to go with a blend solutions with a little better
agreement that previous runs. The GFS is probably the fastest or
most aggressive at bringing precip into parts of the area earlier next
week with ECMWF a little slower and the Canadian yet the slowest.
They all agree on high pressure dominating the weather pattern
Sunday with dry conditions and the start of a warming trend. The
high will slowly drift toward the east coast early in the week. As
it does the flow at the surface will become more southerly. This
will not only help start a warming trend but it opens up the gulf
and dew point rise. In the upper levels a spoke of energy is ejected
out the main trough over the southwest...which has a closed low
which is slow to move due to that fact. This will be the first of
several spokes of energy to eject from southwest upper low from mid
to late week. There will also be slow moving cold front That will
move into the area late Wednesday and slowly move through Thursday
as well. This front looks as if it may stall just south of the area
by Friday. It should however scour out the moisture and bring
temperatures back to near normal. We will have to monitor this
closely since it will be in close proximity to the area. We may be
fortunate enough to have a dry weekend but its too far out for any
degree of certainty at this early date.
&&
.AVIATION...
Issued at 638 PM CDT Fri May 3 2019
MVFR ceilings over much of the region may erode a bit from the
southeast this evening, before returning later tonight as another
round of showers overspreads the area. As the showers set in, IFR
or lower ceilings are expected with MFR to occasional IFR
visibilities. Conditions should improve from west to east in the
afternoon, as the showers come to an end.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
UPDATE...DRS
AVIATION...DRS