Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/02/18
Area Forecast Discussion
National Weather Service Grand Junction CO
920 PM MDT Mon Oct 1 2018
.UPDATE...
Issued at 920 PM MDT Mon Oct 1 2018
Despite a notable increase in moisture across western Colorado
and eastern Utah over the past 24 hours, radar indicated very
little activity at mid-evening. With the exception of an area of
showers in the Pagosa Springs area, and another over extreme
northwest Colorado/northeast Utah, radar indicated no activity.
Latest HRRR and other short range models hold off additional
showers until later tonight. Therefore, have adjusted PoP fields
accordingly and have updated forecast to reflect these changes.
&&
.SHORT TERM...(Tonight through Tuesday night)
Issued at 247 PM MDT Mon Oct 1 2018
Deeper moisture in the southwest flow has arrived to southeast UT,
southwest CO and portions of central CO, which has resulted in
scattered showers and expansive cloud cover. Across northeast UT
better surface heating below steep midlevel lapse rates is allowing
for isolated thunderstorms to develop. There should be a gradual
decrease in showers and storms this afternoon with a lull in the
precipitation this evening. Chances should increase around and after
midnight as several vorticity maximas associated with the remnants
of Hurricane Rosa move over the region. The wind speeds will also
increase out of the southwest focusing the upslope flow over the San
Juan mountains. The last of the vorticity maximum should track over
the forecast area tomorrow evening followed by relatively drier air
that advects in from the southwest. The enhanced lift coinciding
with the deeper moisture should increase the potential for heavy
rainfall. The start of the Flash Flood Watch has been adjusted to
account for the slightly earlier arrival of precipitation late
tonight. The watch has also been expanded to include the rest of
southwest CO and southeast UT. Rainfall amounts are still expected
to generally be around 0.5 to 2 inches with locally higher
amounts of 4 inches within the watch area. The higher amounts
should be confined to the San Juans and the greatest flood
potential will be in and near the more recent burn scars.
.LONG TERM...(Wednesday through Monday)
Issued at 247 PM MDT Mon Oct 1 2018
On Wednesday the closed midlevel low pressure off the coast of CA
will begin to come onshore and weaken into an open wave. The deeper
moisture and associated lift appears to focus mainly over northeast
UT and northwest CO, while the remaining areas get to dry out with
the exception of isolated showers. That wave continues lifting
northeastward on Thursday pushing a cold front through the region.
The 700 mb temperatures may drop as low as 1.5 C causing snow levels
to drop although most of the precipitation will be coming to an end.
Perhaps a few inches of snow are possible in the highest elevations
of the San Juan and Elk mountains by mid day Thursday. On the heels
of that system another shortwave trough tracks over the northern
Rockies bringing another cold front through the area. The 700 mb
temperatures get to near freezing and there may be some minor
precipitation as that front advances eastward mostly during the day
Friday. The snowfall may be minimized given the relatively high sun
angle this time of year during the day. Perhaps the highest peaks in
the Park Range could receive some snow. Yet another shortwave trough
digs over the Four Corners and eventually closes off this weekend.
This system will bring cooler air to the area and widespread
precipitation. The models are in slightly better agreement with the
evolution of this trough although there is still time to fine tune
the details.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 546 PM MDT Mon Oct 1 2018
Lowered flight criteria including terrain obscuration will become
more common over much of eastern Utah and western Colorado during
the early morning hours of Tuesday. About the only TAF sites not
affected will be KVEL and KHDN in this forecast cycle. Rainfall
will become widespread as tropical moisture moves through the
region. Thunderstorms can not be ruled out but will be isolated in
nature. Expect persistent ILS to MVFR conditions near and south of
a KEGE to KRIL to KTEX line by sunrise through at least mid
afternoon.
&&
.HYDROLOGY...
Issued at 247 PM MDT Mon Oct 1 2018
From 1 to 2 inches of rain with locally higher amounts up to 4
hours are possible across the area Tuesday and Wednesday as the
remnants of Hurricane Rosa travel overhead. A Flash Flood Watch is
in effect from Tuesday morning to Wednesday morning for the San
Juan mountains, especially for burn scar areas in the San Juans
and Uncompahgre Plateau, as well as portions of southwest CO and
southeast UT. The 416, Burro and Bull Draw burn scars should be
impacted.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...Flash Flood Watch from 3 AM MDT Tuesday through Wednesday
morning for COZ017>019-021>023.
UT...Flash Flood Watch from 3 AM MDT Tuesday through Wednesday
morning for UTZ022-028-029.
&&
$$
UPDATE...NL
SHORT TERM...MAC/KJS
LONG TERM...MAC/KJS
AVIATION...TGJT
HYDROLOGY...MAC/KJS
Area Forecast Discussion
National Weather Service North Platte NE
640 PM CDT Mon Oct 1 2018
.SYNOPSIS...
Issued at 309 PM CDT Mon Oct 1 2018
Upper level ridging persists across the southeast and south central
portions of the United States. Meanwhile a large upper level trough
of low pressure is digging southward off the California coast, with
tropical storm Rosa moving northeast just off western Baja. West to
southwest flow aloft will continue across our area tonight into
Tuesday.
&&
.SHORT TERM...(This evening through Tuesday)
Issued at 309 PM CDT Mon Oct 1 2018
Low level moisture continues to linger across western and north
central Nebraska. Low clouds are the result, and have had a
difficult time burning those off today. Surface low pressure will
deepen somewhat along the lee of the Rockies tonight into Tuesday.
As this occurs, southeast winds will increase some, which will keep
the moisture locked in. Any clearing that has occurred late this
afternoon should quickly fill back in tonight as stratus redevelops
across the area. Also anticipating areas of fog to develop late
tonight into Tuesday morning, with both the HRRR and RAP suggesting
visibilities as low as one quarter of a mile across portions of
southwest through central and into north central Nebraska.
Am skeptical that we will clear out as fast as some of the models
indicate for Tuesday. Cloud cover held tough today, and with the
southeast upslope moist flow Tuesday, will side with the mesoscale
higher resolution models which hold the cloud cover in longer. In
fact, central Nebraska may have a hard time clearing at all. This
will be reflected in high temperatures, and have lowered several
degrees across central and portions of southwest and north central
Nebraska.
.LONG TERM...(Tuesday night through Monday)
Issued at 309 PM CDT Mon Oct 1 2018
Expect a big warm up Wednesday. A pre-frontal trough will cross the
area Wednesday morning turning the winds to the west and advecting
drier air east across the area. Downslope flow will promote warming,
with highs approaching near records (lower 90s) across southwest and
central Nebraska. As mentioned the air will be dry as dew points
fall into the 40s behind the pre-frontal trough, with humidity
values dropping into the 20 to 25 percent range across west central
and southwest Nebraska as well as portions of the Panhandle. This
could lead to an increase in wildfire potential. In addition, a cold
front will quickly cross the area Wednesday evening, brining a gusty
wind shift to north-northwest. Mid-level frontogenesis (FGEN) will
increase markedly behind the front Wednesday night, with the
development of rain likely across the Panhandle into north central
Nebraska and a chance elsewhere. Expect the rain to linger into
Thursday, with a decrease by Thursday night as the mid-level FGEN
begins to decrease. Much colder weather is expected Thursday behind
the front with highs ranging from the mid 40s to mid 50s.
Unsettled weather will continue Friday and through the weekend into
the first of next week. Another disturbance will cross the area
Saturday night into Sunday with additional chances for rainfall.
Temperatures will remain below normal, with highs Friday in the 60s
and then 50s for Saturday and Sunday. Both the GFS and ECMWF develop
a deep long wave trough into the Rockies by Monday. This turns flow
aloft to southerly across the Central Plains ahead of the trough,
bringing additional moisture northward and continued chances for
rain.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 639 PM CDT Mon Oct 1 2018
The main aviation concern for the next day will the chance for fog
development across the southern forecast area. At this time, it is
anticipated that fog will only impact the KLBF terminal. Fog could
be dense at times with visibilities dropping to near 1 SM. Best
timing for fog impacts will be between 10Z and 15Z. Fog will quickly
dissipate by mid-morning. VFR conditions will remain at KVTN through
Tuesday afternoon.
&&
.FIRE WEATHER...
Issued at 309 PM CDT Mon Oct 1 2018
Wednesday will be monitored closely for elevated and potentially
near-critical fire weather conditions. As a broad upper ridge
centered over the Southeast U.S. begins to break down, a progressive
trough rides along the northern tier of the country and a closed low
comes on shore in SoCal. At the surface, a strong cold front works
through the forecast area during the afternoon. The current forecast
shows unseasonably warm temperatures in the 80s, wind gusts to 35
mph, and RH as low as 25 percent. The 01/12z suite is in general
agreement with 25kt downslope flow and a thermal ridge pushing temps
to 23C at H85. However, this synoptic pattern including the
downsloping winds is conducive to warmer and drier conditions than
models predict. To make matters more worrisome, the fropa will
create a rapid wind shift around peak heating of the day. Will
highlight potential for elevated fire weather conditions in the HWO
and hit heavily in the FWF.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...Taylor
SHORT TERM...Taylor
LONG TERM...Taylor
AVIATION...Kulik
FIRE WEATHER...Snively
Area Forecast Discussion...UPDATED
National Weather Service Chicago/Romeoville, IL
945 PM CDT Mon Oct 1 2018
.MESOSCALE DISCUSSION...
944 PM CDT
Broad area of convection is moving east across northern Illinois,
with embedded cold pools helping for a slight southeast evolution
as well. Embedded well-defined small linear segments have
presented an isolated 40+ mph wind threat, but these have all
been north of the effective warm front, limiting their severe
weather chances. There has been transient brief rotation as well
but that storm behavior has been even further north of the
boundary and far from ideal for tornadic potential.
The 1014 mb surface low is now located over Kane/McHenry
Counties, with the effective warm front draped east-southeast from
there across the southern metro and very far northwest Indiana.
Storm behavior in the vicinity of the front has been fairly
anemic, probably due to being removed from the stronger forcing
for upward motion with the sheared short wave and mid-level speed
max. Will continue to monitor for some stronger storm potential
with winds mainly near the frontal boundary though as the storms
move through Chicago, however radar and observations show an
outflow boundary propagating out likely indicating less of a
threat. Storms should show a diminishing trend on their southern
periphery through early overnight.
As for rainfall, there has been some training of efficient rain-
producing multicell storms with around one inch of rain picked up
quickly under the first storms in far northern Illinois, and then
additional moderate rain for an hour or two behind that. This has
all been within tolerance of any flash flooding level, though it
will prime conditions some for more probable episodes of rain
later this week.
MTF
&&
.SHORT TERM...
209 PM CDT
Through Tonight...
The threat for severe weather continues to be the primary forecast
concern in the near term. Low pressure is analyzed over south
central Iowa this afternoon with a warm front draped east across
portions of northern Illinois. Across the local forecast area, the
front stretches from near Pontiac, IL to Rensselaer, IN as of
about 300 pm CDT. Extensive cloud cover has been in place north of
the front through the day, while south, early clearing has given
way to a developing cumulus field in the warm sector. Modest
MLCAPE of 600-1000 J/kg will continue to build across the warm
sector this afternoon. Meanwhile, large scale ascent will increase
across the region in response to a sheared vort max racing east
across the plains and Upper Midwest in addition to left exit
region of the upper jet moving across the area. Ongoing area of
showers and thunderstorms within warm air advection across eastern
Iowa into southern Wisconsin will continue to gradually shift
east in response, but could also see some isolated to widely
scattered thunderstorms developing along the surface warm front in
the local CWA as it lifts to near the I-80 corridor late this
afternoon. Models continue to paint different pictures on the
possibility of discrete activity along the warm front late this
afternoon and early evening, thus confidence continues to remain
lower with respect to these earlier storms. Early afternoon
satellite imagery does not yet show much in the way of robust cu
growth and thickening cirrus is inhibiting insolation. Still,
will have to closely monitor this area over the next several hours
for possible convective initiation. Early evening forecast
hodographs from the RAP show cyclonically curved wind profiles
with moderately strong deep layer shear overspreading the region
supporting at least a supercell threat in addition to a small
tornado threat. Storm motions appear to run largely parallel to
the orientation of the warm front which appears concerning from a
severe/tornado perspective.
Surface low is expected to shift east across northern Illinois
mid to late this evening, likely between the I-80 and I-90
corridors and, along with the trailing cold front, will serve as
the focus for the greatest coverage of thunderstorms this evening.
Given the strong forcing, storms mode should become linear with
time and the primary severe threat will transition to mainly
damaging winds. Main change in the forecast was to delay slightly
the timing of the cold front later into the evening.
Deubelbeiss
&&
.LONG TERM...
209 PM CDT
Tuesday through Monday...
The extended period continues to look rather active, especially
Wednesday night into early Thursday and again late Friday and into
the weekend.
A cold front will drop south across the area into Tuesday morning
before stalling out over central IL during the day. As it does so,
some lingering showers and possibly a thunderstorm may linger
during the morning, especially south of I-80, but the chances for
showers will wane by the afternoon. While the chances for precip
will be on a downward trend, it does appear that lower level cloud
cover will hang on over the area into the afternoon, before
scattering some later in the day. Expect high temperatures on
Tuesday to range for the mid 60s north to around 80 towards
central IL and IN.
An upper level impulse is forecast to dig southeastward across
British Columbia later Tuesday, before shifting eastward across
the northern High Plains into Wednesday. This disturbance will
induce an area of surface low pressure over the Dakotas Tuesday
night, and should then track east-northeastward into south
central Ontario by early Wednesday evening. As this occurs, the
cold front settling just to our south on Tuesday will quickly
be driven back northward as a warm front early Wednesday. While
there is a small chance of a couple of scattered showers or
storms will the approach of this warm front Tuesday night, it does
appear most of the area will remain dry during this period.
Much warmer, and breezy conditions are likely to set up over the
area on Wednesday as the surface low moves over MN. South-
southwesterly winds could gust as high as 40 mph on Wednesday in
response to the strengthening wind field across the region. These
winds will also transport an unseasonably mild airmass over the
area during the day. With 925 mb temperatures likely to be around
24 degrees C, we will likely experience surface highs well into
the 80s Wednesday afternoon.
Another cold front, associated with the strong low shifting over
Ontario Wednesday night, will push southward over the area
Wednesday night into early Thursday morning. This front could
produce a few thunderstorms over the area as it moves towards the
area Wednesday night, but due to the poor diurnal timing of the
front, it appears the severe threat will be on the lower side as
storms will likely be in a weakening phase as they move into the
area.
Thursday then looks to be a mainly dry day, expect for the
possibly of some lingering shower and storms in my south. Otherwise,
cooler conditions (back into the 60s to low 70s) are likely on
Thursday.
Thursday night through at least early next week it appears the
area could be entering an even more active weather pattern. Model
and ensemble forecast guidance continues to support the
development of a negative PNA-type pattern as a large trough digs
over the western CONUS and an upper level ridge builds over the
east. This type of amplified pattern is a fairly classic one for
producing active weather over the central CONUS due to an active
southwesterly upper level jet over the region. Also, given that
this larger scale pattern may also remain locked in place for
a few days this weekend into next week, it appears that we could
experience several waves of shower and thunderstorms during this
period.
While there is higher confidence in active weather over the
central portion of the county this weekend into early next week
due to larger scale pattern, there still is a good amount of
uncertainty on the smaller scale details, such the track of
individual areas of low pressure, and the actual placement of
surface frontal boundaries. These smaller scale details will
certainly play a role in determining the best focus and timing
for thunderstorms with heavy rainfall and possible flooding.
Additionally, temperatures could be tricky during this period,
with the possibilities for some roller coaster type temperatures
as frontal boundaries waver near the area.
This period will need to be watched in the coming days. The
potential exists for some areas nearby to receive several rounds
of heavy rainfall, and given that some area rivers are already
high, flooding could become a significant concern for some. Also,
given the strong atmospheric dynamics, some areas nearby could
see some strong or severe thunderstorms this weekend.
KJB
&&
.AVIATION...
For the 00Z TAFs...
Main concerns in the near term continue to be with the
thunderstorm potential this evening, though a slight delay is
appearing likely. Latest radar imagery showing much of any
development still situated well west of the terminals at this
time. Although some scattered showery development may occur
through mid evening, the more widespread and stronger thunderstorm
development will likely not arrive until late this evening and
overnight hours. Given the delay, there is some potential for
lower intensity of storms tonight. Window of thunderstorm
development will then shift east overnight, with a drying trend
likely into early Tuesday morning. VFR ceilings this evening will
lower overnight, and continue this trend into early Tuesday
morning with MVFR and IFR ceilings expected. Winds will vary
through the period, with this most prevalent this evening. Then
anticipate a shift to more of a northerly direction Tuesday
morning.
Rodriguez
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...None.
IN...None.
LM...None.
&&
$$
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Area Forecast Discussion
National Weather Service Shreveport LA
1001 PM CDT Mon Oct 1 2018
.UPDATE...
Very isold convection across eastern portions of north LA. Expect
this to diminish before midnight./07/.
&&
.PREV DISCUSSION... /issued 642 PM CDT Mon Oct 1 2018/
AVIATION...
Widely scattered diurnal convection will begin to dissipate with
setting sun. A few showers around ktyr terminal, with heavier
showers movg north of the ktyr and kggg terminals, and other
terminals likely not affected by nearby convection attm. Patchy
fog and possible low clouds could affect all areal terminals
overnight, with best potential for dense fog at ktyr terminal
where wet ground and high sfc rh values in place. Fog may be
limited at some spots by presence of mid and upper lvl clouds
overnight. Aftn convection Tue very isold if at all, with
southerly winds near 5 kts and scattered cumulus clouds./07/.
PREV DISCUSSION... /issued 354 PM CDT Mon Oct 1 2018/
SHORT TERM...
The latest mid-level analysis indicates a broad 500mb ridge
centered across the northern Gulf and extending from Texas across
the ArkLaTex/ArklaMiss eastward into the Carolinas. Locally, there
are a pair of disturbances (vort maxes), the first located across
northwestern Louisiana and the second in southeast Texas near
Houston. At the surface, high pressure off the mid-Atlantic
extends southwestward across the southeast and into Texas. The
remnants of a weak frontal boundary extends from Monroe
southwestward to Lufkin. The latest RAP mesoanalysis indicates an
area of 3000-3500 J/kg CAPE extending from Lufkin northeastward
into northern Louisiana and southern Arkansas. An instability
gradient has setup across our area with weak weaker instability
(1000-1500 J/kg) in southeastern Oklahoma and northeast Texas.
The pair of mid-level disturbances will shift across the area
this afternoon and tonight, providing a source of lift for
showers and thunderstorms. The best coverage of showers and
thunderstorms is expected to coincide with strongest instability
from Lufkin eastward into northwest and central Louisiana as the
first piece of mid-level energy moves across the area this
afternoon and early evening. This will allow for scattered
showers and thunderstorms for these locations with more isolated
showers and storms north and west of Shreveport.
Tonight, with instability diminishing with the loss of heating,
showers and thunderstorms will mostly diminish. Have left in a
slight chance of showers overnight as the second disturbance from
Houston moves into central Louisiana and provides some lift for
areas primarily south and east of Shreveport. Fog will be most
prevalent in locations which see rainfall this afternoon with
patchy fog anticipated elsewhere. Lows overnight will range from
the upper 60s across southeast Arkansas and McCurtain County,
Oklahoma to the lower 70s southward.
Tomorrow and tomorrow night, the mid-level ridge will continue to
edge westward as it becomes centered across the ArkLaMiss. This
will serve to suppress showers and thunderstorms for the majority.
GFS/NAM show some inconsistency in bringing the next mid-level
disturbance across the area tomorrow, ranging from its location
being in east Texas (NAM) to northern Louisiana (GFS). Given an
unstable environment paired with forcing and little or no
coverage indicated by mesoscale models, just a slight chance of
thunderstorms is predicted across the Four State region. Less
cloud coverage is anticipated on Tuesday, contributing to warmer
high temperatures ranging from the mid to upper 80s across the
area. Lows Tuesday night are expected to be mostly in the lower
70s. /04/
LONG TERM...
The much advertised upper level ridge of high pressure will build
heights aloft and continue around 590-592dam for the ArkLaTex
through the end of the work week allowing for warmer temperatures
areawide. High temperatures will range from the mid 80s to around 90
at least through Friday. Then we will scale back the heat with
additional clouds and lowering heights aloft as the long wave trough
out West nudges the upper ridge out of the picture for us.
Surface winds will continue out of the S/SE through the weekend so
while the Gulf moisture may support diurnally driven convection each
day along weak sea-breeze boundaries, the upper-ridge expansion
aloft will limit the convective coverage from isolated to maybe
widely scattered along a South of I-20 during the work week.
As the upper ridge shifts eastward, the deep southerly flow will
increase wind speeds on the both the surface and aloft ahead of a
strong cold front which will amp up the moisture being imported into
the area. Scattered showers and thunderstorms will do much better
inland off the Gulf on Saturday with the center of the ridge much
farther East. Then shower and thunderstorm activity on Sunday will
be edging in from the West and still off of the Gulf with the long
wave encroachment. In any event, it will be a bit cooler with the
lower heights aloft and the added clouds and rain areas even more so
into Monday as the front gets closer. /24/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 72 89 72 90 / 10 20 10 10
MLU 72 90 71 90 / 20 20 20 10
DEQ 69 86 69 88 / 10 20 10 10
TXK 70 86 70 88 / 10 20 10 10
ELD 71 88 71 90 / 20 20 20 10
TYR 70 86 71 88 / 10 20 10 10
GGG 71 88 71 89 / 10 20 10 10
LFK 71 88 72 89 / 10 20 10 20
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...None.
LA...None.
OK...None.
TX...None.
&&
$$
Area Forecast Discussion
National Weather Service Tucson AZ
350 PM MST Mon Oct 1 2018
.SYNOPSIS...Widespread showers with occasional thunderstorms into
Tuesday especially west to north of Tucson. Gusty winds should also
occur Tuesday. Isolated showers and thunderstorms Wednesday, then
mainly dry conditions Thursday into Saturday. A chance of showers
and thunderstorms returns early next week with gusty winds and
continued below normal temperatures.
&&
.DISCUSSION...Scattered showers and thunderstorms were occurring at
this time across Greenlee, Graham and Cochise Counties east of
Tucson. Other isolated showers producing very light rain were
northwest to north of Tucson. Several HRRR solutions suggest that
showers/tstms east of Tucson will gradually decrease in coverage
early this evening. Thereafter, the focus of attention will turn
westward as scattered to numerous showers with embedded
thunderstorms move into western sections of this forecast area later
this evening. The bulk of rainfall later tonight into Tuesday should
occur northwest to north of Tucson. Isolated to scattered showers
and thunderstorms should occur elsewhere Tuesday afternoon into
Tuesday night. Gusty generally southerly winds will also prevail
Tuesday afternoon into evening.
Rainfall chances begin to decrease Wednesday as the bulk of deeper
moisture moves north to east of this forecast area. However, an
upper trough over the area combined with lingering moisture will
translate into isolated showers and thunderstorms Wednesday. A broad
trough will prevail over the western CONUS Thursday through
Saturday. Various 01/12Z numerical weather prediction solutions
depicted impulses embedded within this trough will move eastward
into the central/southern Rockies. However, the models also suggest
that measurable rainfall will primarily occur from the Mogollon Rim
northward into Utah. Thus, a slight chance of showers/tstms
continues Thursday mainly across the White Mountains, then have
maintained dry conditions across much of this forecast area Friday
into Saturday.
Thereafter, the deterministic 01/12Z GFS/ECMWF and associated
ensembles were fairly similar with depicting a sharply deepening
upper trough over the southwestern CONUS Sunday into Monday. A
chance of showers/tstms returns early next week, especially east of
Tucson. A slight chance of showers/tstms is also warranted from
Tucson westward into the Tohono O`odham Nation and south central
Pinal County. Have maintained precip-free conditions across western
Pima County Sunday into Monday.
If subsequent model solutions remain consistent, then would not be
surprised to see PoPs adjusted upward markedly versus this forecast
issuance. The markedly lower heights/ thicknesses suggest that
accumulating snowfall may occur by next Monday across the higher
White Mountain peaks. The very tight mid-level gradient progged via
these solutions also suggests that gusty southwest to west winds
especially during the afternoon hours.
A warming trend will occur Tuesday especially from Tucson westward
into western Pima County, but only very minor temp changes are on
tap Tuesday versus Monday across eastern sections. Additional
warming is on tap Wednesday with high temps trending closer to
seasonal normals. Expect no significant change in daytime temps
Thursday thru Saturday, then cooler temps are increasingly likely
Sunday and especially next Monday.
&&
.AVIATION...Valid through 03/00Z.
Scattered -TSRA/-SHRA east of KTUS ending this evening, then
numerous -SHRA and isolated -TSRA mainly west to north of KTUS later
tonight into Tuesday afternoon. Expect MVFR conditions and
occasional IFR conditions. Otherwise, cloud decks mainly 4k-10k ft
AGL. Surface wind variable in direction mainly less than 12 kts into
Tuesday morning, then surface wind generally southerly 10-20 kts
with gusts near 25 kts Tuesday afternoon. Aviation discussion not
updated for TAF amendments.
&&
.FIRE WEATHER...Widespread showers with occasional thunderstorms
through Tuesday. The higher rainfall amounts will likely occur west
to northwest of Tucson. Isolated showers and thunderstorms Wednesday
especially north of Tucson, then dry conditions across much of the
area Thursday into Saturday. A chance of showers and thunderstorms
returns Sunday into Monday mainly from Tucson eastward. Gusty south
winds to occur Tuesday and gusty southwest winds early next week.
Otherwise, 20-foot winds will be terrain driven mainly less than 15
mph.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...
Flash Flood Watch through late Tuesday night for AZZ501-502-505-
506.
&&
$$
DISCUSSION...Francis
AVIATION...Hardin
FIRE WEATHER...Hardin
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