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Area forecast discussion...updated 
National Weather Service Fort Worth Texas
728 am CDT Tuesday Jun 30 2015

Update...
despite the low level jet veering and weakening...and the overnight cluster
of showers and storms moving away from the better Theta-E
axis...they continue to persist on latent instability between
2000-3000 j/kg across central Texas. Have updated to increase rain
chances rain chances from Hillsboro toward Waco and Mexia for
this morning. Rainfall amounts will not be overly high as
continued weakening occurs through middle morning.

Residual outflow boundaries and a weak mesoscale convective vortex from this system will
surely be a player in where convective initiation occurs this
afternoon and early evening.

05/

&&

Aviation...
/issued 630 am CDT Tuesday Jun 30 2015/
outflow from earlier thunderstorms served as the focus for new
convective development in the Dallas area a few hours ago. These
storms have propagated south...aided by a modest low level jet and
a weak shortwave aloft. Activity should linger for another couple
of hours before bl mixing and disruption of the low level jet
leads to its demise. For now...it appears that vcsh in the kact
taf should suffice with the expectation that storms will dissipate
before reaching the Waco area....but we will keep an eye on radar
trends.

Isolated convection will be possible during peak heating late
this afternoon...but probabilities are too low to include in any
of the North Texas tafs. VFR conditions and south winds will
continue to be the rule...with the outside chance of mesoscale
boundaries and/or isolated convection interrupting an otherwise
quiet weather day.

30



&&




Previous discussion... /issued 233 am CDT Tuesday Jun 30 2015/
we will continue to see a diffluent north flow pattern over the
Central Plains into early Wednesday...before flat ridging arrives
later Wednesday into Thursday for a brief reprieve in isolated to
scattered convection. Currently...an elevated 925mb-850mb front
extended from near the I-20 corridor up into southeast OK/SW Arkansas this
morning. A Theta-E axis between 925mb-700mb was expected to be
situated just off the southeast edge of the elevated front today.

One little cluster of strong storms from McKinney to Greenville
continue to be fed by a 25-30 knots south-southwesterly low level jet and will continue to
migrate south-southwest into the Richer Theta-E airmass through sunrise.
Current high res models continue to struggle with activity once
again in the weak diffluent flow aloft and were deemed pretty much
unusable this morning. Current cluster of storms over our NE counties
is expected to weaken toward sunrise as current modest low level jet
weakens. I will still carry 20-30 probability of precipitation generally across the southeast
half of the County Warning Area today as numerous old outflow boundaries will
exist with forcing from a subtle shortwave rotating southeast toward the
northwest Gulf of Mexico. With strong instability and high Theta-E lapse
rates expected...a few strong to brief severe microbursts and
very small hail are possible. Locally heavy rainfall and minor
flooding will be possible due to weak steering currents aloft and
propagation dominating storm movements.

For tonight into Wednesday...have lingered slight chances across
the far southeast counties where the Richer moisture will persist for
another day. A brief dry period will occur Wednesday night through
Thursday evening as some enhancement of ridging aloft and
resultant subsidence occur. However...the eastern Continental U.S. Trough
will amplify once again by Friday into the Holiday weekend...as
the upper ridge axis migrates west out of the area once again.
This longwave pattern change will allow periodic northwest flow shortwave
disturbances to rotate southeast across the arklatex and bring chances
for showers and storms across particularly areas north of I-20 and
east of I-35. It is hard to say how this will affect July 4th
festivities...but the weather definitely bears watching if you
plan on being outdoors this Holiday weekend to watch area
fireworks displays. High temperatures should be slightly below
normal with temperatures in the lower 90s the end of the week into the
Holiday weekend.

A seasonably hot and dry period looks to set up next week...as
amplification of the longwave pattern dampens with broad ridging
setting up from the SW states into the central Gulf states. Highs
in the middle 90s and lows in the 70s are expected with dry
conditions.

05/




&&



Preliminary point temps/pops...
Dallas-ft. Worth, Texas 95 76 95 76 94 / 20 5 5 5 5
Waco, Texas 93 74 93 74 93 / 50 10 5 5 5
Paris, Texas 92 73 92 75 91 / 20 10 10 5 5
Denton, Texas 95 74 94 75 93 / 20 5 5 5 5
McKinney, Texas 93 74 94 75 93 / 20 5 5 5 5
Dallas, Texas 95 77 95 77 94 / 20 5 5 5 5
Terrell, Texas 93 74 93 75 92 / 20 10 5 5 5
Corsicana, Texas 92 74 93 74 92 / 50 10 10 5 5
Temple, Texas 91 72 92 72 91 / 20 20 10 5 5
Mineral Wells, Texas 94 72 95 73 92 / 10 5 5 5 5

&&

Forward watches/warnings/advisories...
none.

&&

$$

30/05

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