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Area forecast discussion 
National Weather Service Huntsville Alabama
401 am CDT Tuesday Jun 30 2015

Discussion...
a line of broken showers/thunderstorms stretching from the middle Atlantic southwestward
into northern MS continues to gradually makes its way eastward this early Tuesday
morning. A cluster of thunderstorms associated with this line is currently
tracking eastward across portions of northwest Alabama...and is showing little sign
of weakening at least for the next few hours. These storms may very
well move into the hsv metropolitan area before daybreak...and result in
gusty winds...very heavy rainfall and frequent lightning for a brief
period of time before weakening/moving off to the east...provided they
somewhat hold together. This is just the first round/wave of
showers/thunderstorms xpcted to develop along/ahead of a weak frontal
boundary positioned from the Ohio Valley southwestward into the middle plains
states. With an unseasonably strong upper trough pattern in place
across the eastern 2/3 of the Continental U.S....multiple waves rotating along the
base of the upper trough may push the surface boundary a bit closer to
the local area later today. Latest model runs are fairly consistent
with the second/stronger of the these upper disturbances traversing
southeastward across the region late this afternoon. With latent energy or
buoyancy increasing coupled with low/middle level inflow in the 30-40kt
range and the freezing level falling below 10k feet...the threat is
definitely there for some strong/localized severe thunderstorms...capable of
large hail and damaging wind gusts. Convection then looks to taper
off to the S/east during the evening...especially with the loss of
daytime heating.

Unfortunately the forecast does not look to improve going into middle
week. In fact...the latest model suites remain fairly aggressive
with additional upper disturbances xpcted to move across the region
going toward the end of the work week. The stronger of these next
upper waves looks to impact the area from late Wednesday into Thursday...and
with forecast time heights indicating a nearly saturated column
above 300 mb...see little reason why showers/thunderstorms will not become more
numerous in nature. Strong to perhaps even marginally severe thunderstorms will
be a threat each day into Thursday...with the higher threats being gusty
outflow winds and frequent cloud to ground lightning. Multiple
rounds of heavy rainfall impacting the same general locations may
also begin to warrant a localized flooding threat...mainly for
creeks...streams...low lying areas and some roadways.

In keeping with the gloomy weather forecast...this pattern does not look
to deviate much heading into the Fourth of July weekend. The latter
half of the global model runs continue to suggest additional upper
disturbances tracking southeastward across the region embedded within a
persistent northwesterly flow regime. Multiple frontal boundaries at the surface
also look to approach the area from the northwest and stall either just to
the north/in vicinity of the central Tennessee Valley over the next several days. The one
bright spot may be toward day 7 where the models hint at a weak cold
front possibly making its way through the area southward...thereby helping
to offset this unseasonably wet period. Hopefully this trend stays
fairly persistent with future model runs over the next few days.

09

&&

Aviation...
/issued 1204 am CDT Tuesday Jun 30 2015/
for 06z tafs...will continue with VFR conditions in the short term
and have added in a thunderstorms in the vicinity for mean sea level at the beginning of the taf and
around 09z for hsv. With scattered rain showers/thunderstorms and rain building eastward
toward mean sea level by around 09z...have added in a 5sm thunderstorms and rain mention until at
least 12z Tuesday. Expect that scattered rain showers/thunderstorms and rain will continue from
17z- 21z at both hsv and mean sea level and will slowly end precipitation by around
23z...with VFR conditions expected through the end of the forecast
period.

Tt

&&

Preliminary point temps/pops...
Huntsville 90 69 88 71 / 50 20 60 60
Shoals 90 69 89 72 / 50 20 60 60
Vinemont 87 67 86 70 / 50 20 60 60
Fayetteville 86 66 85 69 / 50 20 60 60
Albertville 87 68 83 70 / 50 20 60 60
Fort Payne 87 66 85 69 / 50 20 60 60

&&

Hun watches/warnings/advisories...
Alabama...none.
Tennessee...none.
&&

$$

For more information please visit our website
at weather.Gov/Huntsville.

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