Forecast Discussions mentioning any of
"ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 05/15/22
Area Forecast Discussion
National Weather Service Indianapolis IN
1138 PM EDT Sat May 14 2022
...Updated Aviation Discussion...
Issued at 1000 PM EDT Sat May 14 2022
Surface analysis late this evening shows a weak trough of low
pressure tretching from NE OH across Indiana to a weak area of low
pressure in place ovet he soutern plains. This trough was poorly
organized. GOES16 shows convective debris clouds lingering across
Indiana...with radar showsing the remnant convection diving south
into southern Indiana. Aloft a stream of Pacific mositure and
dynamcis was pushing across the western plains to the Ohio
valley...with weak wave of forcing embedded within the flow. Earlier
convection has resulted in surfac temps in the 60s amd cold pools
from earlier convection are predominate.
Overnight alack of forcing remains in pace and convective debris
clouds are expected to continue to dissipate. Forecast soundings
remain dry as do the time heights. Thus with no forcing...partly
cloudy skies will be expecte along with lows in the upper 50s. Given
current dew point depressions...some fog potential will be in place
espcially with the rain that occured today.
.Short Term...(This evening through Sunday night)
Issued at 125 PM EDT Sat May 14 2022
Flow is weak across the area today, between a dying upper low in the
Southeast and a poleward lifting midlevel low north of the Dakotas.
Latest ACARS sounding has 20-25 knot max flow in the troposphere.
Surface winds are light and non-uniform, with a few corridors of
convergence inferred. The most pronounced is now in western
Indiana with the dying and very weakly baroclinic front tied to
aforementioned lifting wave. This is where convection should
become most concentrated later this afternoon.
Weak shear should result in short-lived single- and multi-cells with
the main hazard being brief strong to potentially damaging wind
gusts. Hail is possible, but storm mode and relatively weak midlevel
lapse rates should preclude a more substantial hail concern.
Convection should tend to propagate southeastward given modest
southerly mean flow convergent on the south side of cold pools.
Storms should propagate southeast of the area and diminish later
Please refer to mesoscale updates for more details on convective
evolution through the afternoon and evening.
Meanwhile, upstream Pacific jet will migrate eastward carving out a
more pronounced shortwave trough at the base of the aforementioned
Canadian low. This will offer stronger winds aloft, more shear, and
forcing for ascent for our region tomorrow, leading to another round
of convection. The thermodynamic/kinematic environment will be
supportive of severe storms with damaging winds being the primary
threat. There is still considerable uncertainty on upstream
convective development Sunday afternoon, and MCS potential with a
more organized wind threat into the area by evening. Low-level jet
orientation may support more of a southeastward propagation, that
would result in a path just southwest of the area. Even then, at
least scattered development would be possible further north into our
area, especially along the advancing front. Details on convective
evolution and threats will become more clear tonight and tomorrow.
.Long Term...(Monday through Saturday)
Issued at 125 PM EDT Sat May 14 2022
Post-frontal continental air mass will be drier and temperatures
will fall to near climo for mid-May early next week. This will
continue within mean northwesterly flow pattern until mid-week when
deamplfying ridging nudges in. Even then, one or more
perturbations in the flow will offer increased chances for showers
and thunderstorms Tuesday night and beyond. At least initially,
we`ll be in a warm moist advection pattern with deeper moisture
and anomalous precipitable water values moving into the area and
lingering through the end of the week. Shear and especially
instability looks sufficient for strong to severe thunderstorm
potential, but this will depend on convective evolution. Multiple
rounds of convection are possible during this period. This may
lead to some concern for flooding.
.Aviation...(06Z TAF Issuance)
Issued at 1138 PM EDT Sat May 14 2022
* Mainly VFR Conditions will be expected this TAF period.
* Possible brief MVFR Fog overnight
Outflow boundary cold pools were predominate across Central Indiana
late this evening. Dew point depressions near 5F along with
dissipating cloud cover...light winds and recent rain may lead to
diurnal fog development overnight as RHs approach 90%+. With little
to no forcing overnight expect skies to continue to gradually clear.
Have included a tempo group near max rh hours to account for
Forecast soundings on Sunday again suggest attainable convective
temps and HRRR shows an area of TSRA pushing across the forecast
sites during the afternoon. Confidence remains low for specific
timing on any storms. Thus have used a window of VCTS during the
peak heating hours in the afternoon to account for this until
Furthermore a strong wave aloft is hinted at arriving on Sunday
evening. Forecast soundings here trend toward deep saturation during
the late evening hours. Thus have again included a continued window
of VCSH to account for possible showers.
Area Forecast Discussion
National Weather Service Phoenix AZ
442 PM MST Sat May 14 2022
Updated Aviation section.
.SYNOPSIS...High pressure overhead will result in well-above normal
high temperatures through the rest of the weekend, with the lower
deserts reaching the middle 100s. High temperatures will remain
around 100 through the middle of next week. The afternoon
temperatures will result in a moderate heat risk for the heat
sensitive group and the necessary precautions should be taken.
Seasonably dry conditions will persist through the period with
mostly clear skies.
Latest objective analysis depicts a ridge of high pressure situated
overhead. Latest PHX ACARS sounding shows an additional 2-5C of
warming compared to 24 hours ago. As a result, temperatures
across the lower deserts this afternoon should be significantly
warmer compared to the highs from yesterday, topping out in the
102-105 degree range across most of the lower deserts. High
temperatures on Sunday are still projected to be slightly warmer
as the ensembles show the low-levels warming another degree
Celsius and thus readings are likely to top out in the 103-107
range. The NBM probability of tying/breaking daily record highs on
Sunday, is still low (<30%), although higher than the past couple
of days. By late in the day on Sunday through Monday, a weak
shortwave trough currently located more than 300 miles off the
southern California Coast will approach the region. This will
bring in an increase in breeziness as well as scattered to broken
high-level clouds. Across portions of SE California, especially
across Imperial County, downsloping westerly flow will likely
result in wind gusts in excess of 20-25 mph, especially after
sundown on Sunday.
The aforementioned shortwave trough will result in a slight
cooldown in temperatures for Monday, with highs mostly in the
lower 100s. Temperatures through the middle of the week will
remain mostly steady, with highs hovering or slightly surpassing
100 degrees across the lower deserts as a zonal flow pattern
establishes itself over the area. Therefore, given that
temperatures are likely to be in the triple digits through the
middle of next week, a moderate heat risk will be in place across
most of the lower deserts, including the population centers, and
thus the proper heat precautions need to be taken.
It is still looking likely as we head towards the end of next week
that high temperatures will fall back below 100 degrees as a deeper
trough digs across the western CONUS. There is still significant
variance amongst the ensembles in terms of the degree of
amplification and positioning of the trough, however, there is
enough confidence of a cooldown in addition to bringing an increase
in winds. Just the magnitude of the cooling and the winds still
remains to be seen. Seasonably dry conditions will continue through
the forecast period with no precipitation in sight unfortunately.
.AVIATION...Updated at 2341Z.
South-Central Arizona including KPHX, KIWA, KSDL, and KDVT; and
Southeast California/Southwest Arizona including KIPL and KBLH:
A ridge of high pressure centered near the southern tip of Baja
Mexico will keep dry and stable conditions in place through
Sunday. Light winds are in place through much of the troposphere.
A weak upper trough centered west-southwest of KSAN will move
inland during the day Sunday. It will have little impact on the
sensible weather with just some minor cirrus. But, winds
above the surface will slowly strengthen overnight and during the
day Sunday. At the surface, familiar warm season diurnal patterns
will prevail. The most noticeable difference from today will be
minor southerly breeziness at KBLH in the afternoon.
High pressure over the area will result in well-above normal
temperatures through the rest of the weekend with very dry air
prevailing. Temperatures through most of the forecast will be 5-10
degrees above normal, surpassing 100 degrees most days at the
lower elevations. Min afternoon RHs values will be less than 5%
through Sunday, and only improving to 10-15% during the middle of
next week. Overnight RH recovery will be poor through the rest of
the weekend, only topping out in the 15-25% range. There will be
a slight improvement in Max RHs next week with overnight shallow
moisture fluxes from the Gulf of California. Areas near the Lower
CO River Valley will see the greatest Max RH improvement, to
around 40-50% by midweek, with elsewhere only to 20-30%. A slight
increase in wind is expected late Sunday, when gusts could
occasionally exceed 20-25 mph, mainly across SE California as a
weak weather disturbance moves across the region. Otherwise,
seasonal winds will prevail, with afternoon gusts commonly between
15-20 mph. Another wind increase, and potentially more
significant, is expected near the end of next week as a stronger
disturbance moves into the western states, which could elevate
the fire danger potential.
Record highs later this week:
Date Phoenix Yuma El Centro
---- ------- ---- ---------
5/14 107 in 1927 113 in 1927 110 in 1927
5/15 107 in 1937 109 in 1937 107 in 1934
5/16 106 in 1997 109 in 1956 108 in 2014
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