Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/19/18
Area Forecast Discussion
National Weather Service Denver/Boulder CO
851 PM MDT Thu Oct 18 2018
.UPDATE...
Issued at 831 PM MDT Thu Oct 18 2018
No major adjustments to the grids at this time. Snow showers
moving through Summit County. Roads wet with icy spots near
the Eisenhower Tunnel this evening. Current forecast of 2-5"
looks reasonable, higher end of that range will be more
localized. Some rain showers may spill out of the foothills and
into the I25 corridor. Most of the showers should stay west of
the interstate and dissipate altogether after midnight. Stratus
deck advancing north and west into Lincoln and southern Washington
early this evening, so will increase the cloud cover there. Most
of this will shift eastward after midnight.
&&
.SHORT TERM...(This evening through Friday)
Issued at 109 PM MDT Thu Oct 18 2018
Water vapor imagery shows a trough that is currently rotating
over Utah with a southwest to northeast oriented jet streak
extending from eastern Arizona to Nebraska. This trough will
slowly move eastward through the night and will be picked up
within the northwesterly flow tomorrow. As this system moves
through Colorado tonight, it will create convective showers mainly
over the central mountains south of Grand Lake through northern
Park County. There is growing confidence in this outcome because
there are convective showers already present over western Colorado
and eastern Utah on visible satellite and radar. Model lapse rates
further support this outcome with values forecast to be between 8
to 9 degrees C per kilometer late this afternoon and into the
early evening. Model trends have continued to increase total QPF
values throughout the day with the HRRR now showing maximum QPF
values in Clear Creak and Summit Counties of around an inch. I
continue to believe these max values are overdone but there is
good reason to think QPF values will be higher than originally
expected. Therefore, I have increased POPs, QPF, and snowfall
amounts such that areas above 10,000 feet can expect 2-5 inches of
snow south of Grand Lake through north Park County. With these
convective showers it is of note that the snowfall rates will be
higher than normal and may be between 1 to 2 inches per hour under
the heavier showers. Travel in this area above 10,000 may become
briefly hazardous from 6pm to midnight.
Flow turns northerly on Friday as the trough departs with gusts
up to 25 mph across the eastern plains tomorrow. Despite the
northerly flow, temperatures will only be a couple degrees
cooler.
.LONG TERM...(Friday night through Thursday)
Issued at 109 PM MDT Thu Oct 18 2018
Friday night upper level high pressure centered over the Pacific
Northwest will begin to move southwest toward Colorado. Flow will
initially be from the north-northwest on Saturday transitioning to
southwesterly flow as the ridge flattens Sunday afternoon. This
flow pattern will lead to warm, dry conditions through the
weekend. Temperatures are forecast to be well above seasonal
normals by Sunday.
Monday mid level moisture is expected to increase as a trough advances
to the east. This will allow for the advection of tropical
moisture into the region in southeast flow. Late Monday into
Tuesday ascent will increase slightly allowing for a slight chance
of showers over the high country and northern border. The
moisture is forecast to spread onto the plains Tuesday afternoon.
This would give most of north central and northeast Colorado a
slight chance of showers with the best chance remaining over the
high country. Warm temperatures will keep rain over the plains
with snow levels above 9,000 feet.
Wednesday the trough is anticipated to progress east as subsidence
forms across the forecast area. Thursday a front will move into
northeast Colorado with the ECMWF showing a secondary trough while
the GFS brings in only a weak trough at the end of the period.
There will be a potential for light orographic snow showers over
the mountains with dry conditions across the plains.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 831 PM MDT Thu Oct 18 2018
VFR conditions will continue through Friday evening. Southerly to
southeasterly winds at KDEN and KAPA should persist through the
evening, strongest at KDEN.
High res models continue to show weak showers pushing off the
mountains through 06z and weakening further as they move
eastward. These could survive enough to briefly drop ceilings at
BJC and APA but no major impacts are expected.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE...Cooper
SHORT TERM...Danielson
LONG TERM...Sullivan
AVIATION...Cooper
Area Forecast Discussion
National Weather Service Burlington VT
957 PM EDT Thu Oct 18 2018
.SYNOPSIS...
A ridge of high pressure will crest over the North Country
tonight, before sliding to the south and east of the region on
Friday. Developing moderate south winds will bring milder and
more seasonable conditions on Friday, with high temperatures
generally reaching the 50s. However, this will be short-lived as
another cold front brings a chance of rain showers Saturday
morning followed by brisk conditions Saturday night into Sunday.
High on Sunday will only reach the upper 30s to lower 40s
across the North Country. Temperatures gradually moderate back
closer to seasonable levels toward the middle of next week.
&&
.NEAR TERM /THROUGH FRIDAY NIGHT/...
As of 957 PM EDT Thursday...Latest RAP analysis shows warm air
advection taking place now. It also seems upper level ridging
did not build in fast enough for a stream of mid to high level
associated with some shortwave energy to be shunted east before
moving south into the US. So now they are moving across Northern
New York and Northern Vermont with temperatures being slow to
fall. With warm air advecting and clouds combating radiational
cooling, have nudged overnight lows up a few degrees and
adjusted hourly temperature trends accordingly. However, no
adjustments have been made to the freeze warning at this time.
The rest of the forecast remains in great shape. Have a good
night.
PREVIOUS DISCUSSION...
As narrow ridge of high pressure shifts ewd and crests over the
North Country this evening, anticipate 2-m temperatures falling
rapidly given very low dewpoints and dissipating stratocu.
Should see temperatures down into the 28-32F range in the
Champlain Valley before midnight, and thus have reissued the
Freeze Warning from 10PM-8AM for the Champlain Valley where
frost/freeze program remains active. That said, winds will shift
into the S-SW overnight, and temperatures should gradually
level out and even slowly rise toward daybreak from the
Champlain Valley west, as low-level WAA regime develops. We are
also monitoring lake induced clouds across wrn NY. It appears
we`ll see stratus move back into the nrn Adirondacks and across
portions of VT after 03Z with onset of low-level WAA. Not
anticipating any precipitation, but have indicated skies
becoming cloudy especially across the nrn Adirondacks with
orographic ascent aiding in the increase in clouds as moisture
from the ern Great Lakes arrives. Lows outside the Champlain
Valley will generally be in the mid-upr 20s.
South winds continue on Friday with temperatures moderating back
into the mid-upr 50s with partly to mostly sunny conditions
developing. The south winds will be moderately strong in the
Champlain Valley, generally south 15-25 mph with gusts to 30 mph
possible. A Lake Wind Advisory may be required for Lake
Champlain.
Continued S-SW low-level flow for Friday night. Appears next
shortwave trough and associated sfc cold front approach the St.
Lawrence Valley by 12z Saturday. As this system approaches, will
see a gradual increase in mid-level cloud cover from W-E, with
30-60% PoPs for light rain showers mainly across nrn NY after
midnight. May see light rainfall amts across St. Lawrence,
generally <0.10". Lows Friday Night mainly in the low-mid 40s,
though a few deeper valleys may see a decoupled PBL with lows
into the upper 30s in spots.
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
As of 338 PM EDT Thursday...A cold front approaching from the
northwest will move through the region Saturday, resulting in
another rather dreary day to start the weekend. The frontal
passage will be accompanied by some scattered rain showers
through the day along with some gusty southwesterly winds ahead
of the front, transitioning to gusty northwesterly winds after
the fropa. Skies will be mostly cloudy to overcast through the
day, and high temperatures will be near seasonable values -
upper 40s to upper 50s. The Saint Lawrence Valley and the
northern Adirondacks will be cooler than areas further east due
to the earlier timing of the frontal passage in the western
portions of the forecast area.
By Saturday night, the front will have cleared the entire
forecast area, allowing for the establishment of brisk
northwesterly flow throughout the North Country. A highly
amplified trough digging over the northeastern US will supply
another shot of unseasonably cold air to the area. Low- and mid-
level temperatures within the base of the trough will be 2 to 3
standard deviations below normal. Temperatures will drop sharply
overnight, bottoming out in the 20s to 30s before dawn. While
the bulk of the rain showers will end after the frontal passage
Saturday, some lingering upslope showers can be expected
overnight. Freezing levels will lower through the night, so a
transition from rain to light snow showers through the night can
be expected at all but valley locations. Accumulating snow
overnight will be confined to the higher elevations of the
northern Adirondacks, Green Mountains, and the Northeast
Kingdom, and should generally stay under an inch in all but the
highest summits.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
As of 338 PM EDT Thursday...The long-term forecast will continue
to feature very changeable but chilly weather as a series of
deep upper-level troughs with associated surface fronts
transport unseasonably cold Canadian-sourced air towards New
England.
Sunday will be the coldest day with gusty northwesterly winds
and temperatures 15 to 20 degrees below seasonal norms. Highs
will generally be in the 30s to near 40, but wind chills will be
colder. Temperatures will moderate slightly as the workweek
begins, but forecast highs mainly in the 40s will still be 5 to
10 degrees below normal. The next chance for precipitation will
be Monday night through Tuesday as the trailing edges of some
Lake Effect snow bands off Lake Ontario are directed towards our
forecast area. Precipitation type would likely vary diurnally
at this point, with some light snow expected in the
overnight/morning hours, transitioning to rain showers during
the daytime hours. It`s too early at this point to hone in
closely on snow accumulations and axis of heaviest precipitation,
but significant accumulations are not expected. By Wednesday,
high pressure will build in and we should be dry once again. At
this point, the end of the week looks to remain dry as high
pressure continues to build, but given the progressive nature of
the upper-flow, confidence that far out is fairly low.
&&
.AVIATION /02Z FRIDAY THROUGH TUESDAY/...
Through 00Z Saturday...Conditions currently VFR at all sites
with mid-level clouds streaming southward from Canada and Lake
Ontario stratus beginning to intrude along the Adirondacks. MVFR
ceilings of 2000 to 2500ft agl are expected at KSLK with
mountain peaks occasionally obscured between 05Z and 12Z.
Additionally, some LLWS may be possible at KSLK between 05Z and
12Z, but it appears it should remain above 2000ft and is not
mentioned in their TAF at this time. Otherwise, visibilities
will remain unrestricted. Winds are currently in the process of
transitioning from west to southwest and will generally be 5 to
10 knots. Winds will slowly increase after 12Z to 10 to 15 knots
with isolated gusts to 25kts, mainly at KBTV and KMSS, around
peak daylight.
Outlook...
Friday Night: VFR. Chance SHRA.
Saturday: Mainly VFR, with local MVFR possible. Chance SHRA.
Saturday Night: Mainly VFR, with local MVFR possible. Chance
SHRA, Chance SHSN.
Sunday: Mainly VFR, with local MVFR possible. Slight chance SHSN.
Sunday Night: VFR. NO SIG WX.
Monday: VFR. Slight chance SHRA.
Monday Night: Mainly VFR, with local MVFR possible. Chance SHRA,
Chance SHSN.
Tuesday: Mainly MVFR, with local VFR possible. Chance SHRA.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...Freeze Warning until 8 AM EDT Friday for VTZ002-005-009-011.
NY...Freeze Warning until 8 AM EDT Friday for NYZ028-035.
&&
$$
SYNOPSIS...Banacos
NEAR TERM...Banacos/Haynes
SHORT TERM...RSD
LONG TERM...RSD
AVIATION...Haynes
Area Forecast Discussion
National Weather Service State College PA
1053 PM EDT Thu Oct 18 2018
.SYNOPSIS...
High pressure will slide by to the south of Pennsylvania
tonight and Friday. A slight warm up will occur before a couple
of cold fronts move through over the weekend. Colder than
normal temperatures but mainly dry weather are expected for the
at least the first part of next week.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
Temperatures near fcst lows now across the north, but still
some wind in spots like AOO and JHW. Also the gradient should
tighten up overnight, especially across the northwest. These
factors should slow down the temperature drop.
Earlier discussion below.
The last vestiges of narrow bands of shallow lake effect strato
cu will drift north and/or diminish across the NW Mtns of PA
through early this evening with clear skies and cold, frosty
conditions to follow for tonight.
As the center of high pressure over the Middle Ohio River Valley
builds east and slides just south of the state late today and
tonight, northwest winds will lighten up a bit across the
southwest half of the state, but still gust into the teens
across the Susq Valley and North-Central Mtns early this
evening.
Nearly ideal radiational cooling will occur tonight. Since the
SE half of the forecast area is still considered to be in the
growing season, Frost Advisories and Freeze Warnings were
issued for late tonight through the morning commute hours Friday
for this part of the state.
Low temps at daybreak Friday (employing a blend of LAMP, HRRR
and NBM data) will vary from the upper 20s in the rural mountain
valleys of central and northern PA, to the mid 30s in the
larger metro areas in the Lower Susquehanna Valley.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
Friday looks be be an overall nice, mid-autumn day with plenty
of sunshine to start, then a gradually increase in cirrus and
altocu clouds from west to east during the afternoon/evening
hours.
Southwest winds will freshen to 10-15 kts in the afternoon with
gusts into the upper teen to low 20s during the afternoon, with
the highest gusts over the Western Mtns.
Temps in the 50s...to near 60F in the SE will be near to
slightly below normal.
Any light rain will hold off until close to midnight west of the
I-99/Route 220 corridor.
&&
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
*A taste of winter Saturday Night-Sunday. Blustery winds, snow
showers, reduced visibility with some accumulation in the higher
elevations.
Light rain showers are fcst spread into central PA Friday night
into Saturday. QPF is less than 0.25 inch through 00Z Sunday. A
more potent shot of cold air will be accompanied by gusty winds
and snow showers Saturday night into Sunday. Light snow
accumulation (<1 inch) is expected in the NW snowbelt and higher
elevations of the Allegheny Plateau into the Laurel Highlands
(along/west of US-219). Wind chills in the low 30s NW to low 40s
SE on Sunday will make it feel more like early December than
late October. Conditions will improve Sunday night into Monday.
A system passing to the north of the area may bring a few light
rain/snow showers to the northern tier on Tuesday; otherwise
anticipate dry wx to last through midweek.
More detail below.
850 mb temps Sunday down around minus 8, thus plenty cold for
snow.
&&
.AVIATION /03Z FRIDAY THROUGH TUESDAY/...
Generally clear skies expected tonight as the wind has decoupled
in most places and will continue to do except perhaps at JST.
On Friday, cirrus will slide in from the Ohio Valley during the
late morning and afternoon, followed by lowering ceilings Fri
night into generally the MVFR range with a chance for light
rain developing mainly after midnight.
.Outlook...
Fri...No sig wx expected.
Sat...AM low cigs/LLWS likely W Mtns. Scattered showers and
areas of mainly MVFR cigs as a cold front pushes SE across the
PA airfields.
Sun...SHSNRA/cig reductions likely NW Mtns before dawn through
the day. Breezy NW wind.
Mon-Tue...No sig wx expected.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
Freeze Warning until 9 AM EDT Friday for PAZ045-046-049>053-
058-059.
Frost Advisory until 9 AM EDT Friday for PAZ019-025>028-
034>036-056-057-063>066.
&&
$$
SYNOPSIS...Lambert
NEAR TERM...Lambert/Martin
SHORT TERM...Lambert
LONG TERM...Martin/Steinbugl
AVIATION...Lambert/Ceru
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
719 PM CDT Thu Oct 18 2018
.AVIATION.../00Z TAFS/
Intermittent rain showers continue to push inland from the Western
Gulf and will impact all TAF sites through the period as a shallow
frontal inversion remains. Most of the periods will be marked by ifr
cigs with DRT and AUS to have better chances to improve to mvfr in
the afternoon. A few heavy showers will be possible after midnight
and may have to consider periods of tempo 1SM vsbys as convective
trends become more apparent.
&&
.PREV DISCUSSION... /ISSUED 708 PM CDT Thu Oct 18 2018/
UPDATE...
Ran a quick update to bump up PoPs a bit in the Hill Country where
light rain continues. So far, rain rates have been around a tenth of
an inch per hour or less with some isolated spots around a quarter of
an inch earlier. This activity will continue to slowly push north
through the evening hours. Latest runs of the HRRR keeps scattered
showers around overnight and will make no further changes at the
present time.
PREV DISCUSSION... /ISSUED 414 PM CDT Thu Oct 18 2018/
SHORT TERM (Tonight through Friday Night)...
Light to moderate showers will continue to affect portions of south
central Texas through Friday night. There is the potential for
moderate to heavy rain overnight with a second and better signal for
heavy shower activity late Friday morning into the afternoon period.
The Flash Flood Watch has been extended in time through Friday
Evening as one to two inches are expected with isolated 5 inches
possible, mainly across the northern Hill Country including Burnet
and Llano Counties within the next 24 hours.
The reasoning of the rainfall totals through Friday night are as
follow: 1) maximum precipitable daily values of 1.9 to 2.4 inches, 2)
coastal low level pressure over Brownsville, increased low level
jet tonight into Friday, upper level short-wave pulses moving across
the region and 5) convergence zone setting up along the I-35
corridor on Friday.
All these features are anticipated to interact with each other in
one way or another, which will result in moderate to localized heavy
showers within the next 24 hours, especially late Friday morning
into the afternoon period. The majority of HiRes and medium models
are in good agreement with this solution. Therefore, confidence is
high with the new rainfall amounts and possibility of flash flooding.
Once again, with saturated soils in place and expected rainfall
amounts, new flash flooding are likely to occur and affect areas
where ponding of water remains. If you live near the Colorado, Llano
and Nueces basins, we highly recommend to closely monitor the
weather conditions for the next few days as most of rainfall amounts
will become runoff.
LONG TERM (Saturday through Thursday)...
A weak frontal boundary will move into the Rio Grande and Edwards
Plateau areas on Saturday with plenty moisture and instability in
place for the generation of scattered showers and isolated
thunderstorms over those areas. As the boundary moves and dissipates
across the northern part of the area, drier airmass should move
across the eastern part of south central Texas for a break of the
rain. The focus for rain remains over the Rio Grande on Sunday with
rain chances returning to most areas from early to middle of next
week. There is a potential for moderate to heavy showers for this
period as an upper level disturbance moves from the four corners
region into the Southern Plains in addition of increased moisture
arriving from the eastern Pacific and a shallow frontal boundary that
manages to push across the Hill Country.
Temperatures are expected to stay below climate normals through the
entire period.
&&
.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry 57 63 59 67 55 / 60 80 50 50 20
Austin Bergstrom Intl Airport 57 64 59 66 57 / 60 70 50 50 20
New Braunfels Muni Airport 58 66 60 68 57 / 60 70 50 50 20
Burnet Muni Airport 54 61 56 65 53 / 90 80 60 50 20
Del Rio Intl Airport 57 68 61 67 59 / 70 40 40 60 40
Georgetown Muni Airport 55 61 56 65 54 / 70 80 60 50 -
Hondo Muni Airport 58 67 62 69 58 / 90 60 40 50 20
San Marcos Muni Airport 57 66 60 67 57 / 60 70 50 50 20
La Grange - Fayette Regional 60 70 60 68 57 / 50 60 50 40 -
San Antonio Intl Airport 59 67 61 68 58 / 70 70 50 50 20
Stinson Muni Airport 60 68 63 69 59 / 70 70 40 50 20
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
Flash Flood Watch through Friday evening for Bandera-Bexar-Blanco-
Burnet-Comal-Edwards-Gillespie-Hays-Kendall-Kerr-Kinney-Llano-
Maverick-Medina-Real-Travis-Uvalde-Val Verde-Williamson-Zavala.
&&
$$
Aviation...Oaks
Short-Term/Long-Term...Hampshire
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
737 PM CDT Thu Oct 18 2018
.SHORT TERM...(This evening through Friday)
Issued at 230 PM CDT Thu Oct 18 2018
Main short term concerns remain light rain threat tonight and
temperature trends.
Nice warm push of air across the western CWA this afternoon with
readings topping out 70-75. The southwest flow will continue into
tonight and may increase as pressure falls/gradient increases ahead
of incoming northern Minnesota front. The upper trough associated
with the front is moving through the Dakotas/Utah region and is
forecast to lift northeast and spread some mid level moisture
across about the southeast half of the CWA overnight. 300K
Isentropic forecast shows lift in a southwest/northeast band
developing over the eastern CWA through about 06z and exiting to
the far east through 15z Fri. Will mention some likely PoPs with
this feature as it moves east. Any QPF amounts should remain light
or generally one tenth of in inch or less. Temperatures should
remain nearly steady later tonight with upper 40s/lower 50s
expected as a southwest breeze continues.
The light rain should exit rapidly to the east after 12z Fri with
clouds clearing from west to east. The initial cold front is forecast
to move to near a KMSP-KRWF line by 18z. Gusty northwest winds are
expected in the wake of the front, 25-30kts possible. Temperatures
will steady or slowly fall over the northwest CWA into the
afternoon, although cloud cover will be sparse.
.LONG TERM...(Friday night through Thursday)
Issued at 315 PM CDT Thu Oct 18 2018
The upper air pattern will remain consistent through early next
week with a ridge across the western CONUS, and a broad trough
over the northeast. This will lead to an up and down temperature
pattern for this weekend, and into early next week. This pattern
will slowly change next week as a powerful jet stream begins to
flatten out the west coast ridge. This ridge will not be as
amplified as it moves eastward, but the milder Pacific air will
eventually take over late next week, along with a more unsettled
period.
Friday night, and into Saturday morning will have the strongest
cold front move through our region in the next 7 days. This front
will cause strong gusty winds to develop late Friday night, and
into Saturday morning. Highs on Saturday will likely be in the
morning with temperatures falling in the afternoon. Although
models have downplayed the strong short wave moving southeast
along this front, there is still enough energy to generate light
rain, changing to light snow Saturday morning. The main area again
will be concentrated in west central Wisconsin, with the chances
tapering off to nothing west of the Twin Cities. A light dusting
is likely around Ladysmith and Eau Claire by Saturday morning as
this system rotates out of the area.
Another front will arrive Sunday night. However, this front is
moisture starved and not as cool as Saturday`s. Therefore, winds
will shift back to the northwest on Monday, with slightly cooler
temperatures.
As mentioned before, the pattern will slowly change late next week
as a powerful jet stream flattens out the west coast ridge. Slowly
our weather will become more unsettled, but at the same time,
milder Pacific air will infiltrate the region.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 737 PM CDT Thu Oct 18 2018
Clouds are beginning to increase in response to a wave coming up
out of Kansas. This will spread light rain into south central MN
shortly after 6z, with it departing the MPX area shortly after
14z. MKT and EAU look to receive light rain from this wave, with
MSP and RNH being on the edge, with all other terminals remaining
dry. Only expect cigs to drop as low as 5k feet with the rain,
with vis remaining VFR as well. For winds Friday, did boost them
several kts, with GFS/NAM soundings both showing gust potential
between 30 and 40 kts at all terminals. Did remove WS mention from
TAFs as it looks very marginal with little in the way of
directional shear.
KMSP...Rain late tonight may stay just southeast of MSP, but left
the mention in for now, but if current HRRR trends continue, will
have to pull that back to a VCSH mention. Confidence is high that
MSP will remain VFR. GFS bufkit soundings show wind gust potential
up near 40 kts by the afternoon, with those sorts of winds
continuing through Friday night.
/OUTLOOK FOR KMSP/
Sat...VFR. Wind NW 25G35kt early, diminishing to 15G25kt in aftn.
Sun...VFR. Wind SW 15G25kt.
Mon...VFR. Wind SW becoming NW 10G20kt.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
&&
$$
SHORT TERM...DWE
LONG TERM...JLT
AVIATION...MPG
Area Forecast Discussion
National Weather Service Tucson AZ
847 PM MST Thu Oct 18 2018
.SYNOPSIS...Mainly dry conditions with a warming trend through
Friday. A chance of showers returns this weekend and into early next
week as a trough of low pressure moves across the area. Expect gusty
east winds at times, especially on Saturday. By the middle of the
new week we should return to dry conditions across much of the
area with less wind.
&&
.DISCUSSION...Weak troughiness from the northern plains back
through northern Arizona continues a dry southwesterly flow at
most levels across SE AZ. Precipitable water still measured below
1/2 inch on the 00Z KTWC sounding. However, with the lower level
easterly/southeasterly flow we`ve seen boundary layer moisture
increase just enough to keep a cu field around. Surface dewpoints
are up 5 to 8 degrees over the past 24 hours, back into the upper
40s to lower 50s. With the easterly flow the HRRR spreads this
across our entire area by mid morning.
We`re still on track for several degrees of warming over the next
48 hours along with increasing moisture bringing showers and
thunderstorms back over the weekend. Please see the previous
discussion below for additional details.
&&
.AVIATION...Valid through 20/06Z.
Isolated -SHRA/-SHSN mainly across the White Mountains northeast
of KSAD into Friday morning. Otherwise, clear skies KTUS vicinity
westward. From KSAD-KDUG line eastward expect SCT-BKN at 3k-7k ft
AGL through Friday morning. Surface wind diminishing overnight,
generally easterly 5-12 kts with occasional gusts mainly at KTUS.
Aviation discussion not updated for TAF amendments.
&&
.FIRE WEATHER...Dry conditions through Friday except for a slight
chance of showers mainly across the White Mountains. There is a
slight chance of showers across much of southeast Arizona this
weekend. A few thunderstorms may also occur Sunday afternoon. A
slight chance of showers continues Monday into Tuesday mainly east
of Tucson, then dry conditions for much of the area next Wednesday.
Expect gusty east to southeast winds at times into this weekend,
with the strongest winds occurring Saturday. Thereafter, 20-foot
winds generally terrain driven under 15 mph Monday into Wednesday.
&&
.PREV DISCUSSION...Low clouds in the Upper Gila River Valley
south into portions of northeast Cochise county have not lifted or
dissipated much today. Safford has been reporting cloud ceilings
as low as 3 thousand feet AGL all day. Latest models suggested
that this cloudiness will remain in place again tonight and early
tomorrow. Otherwise, the area will be in between systems again
Friday. Both the ECMWF and GFS models develop a weak upper low off
the southern California coast by Friday night. Models track this
upper low north along the coast and then inland through
northern/central California on Sunday. Precipitation, mainly rain,
was progged to develop across parts of Arizona Saturday afternoon
into Sunday. Thereafter, the system tracks through the Great
Basin region on Monday and through the Rockies by early Wednesday.
Expect some lingering showers Monday into Tuesday as the system
passes north of the area. Overall, a warming trend will continue
through Saturday. High temperatures will peak Saturday a few
degrees above normal, followed by some cooling on Sunday into
Tuesday.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...None.
&&
$$
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