Your Weather

To update your location please enter your ZIP code, city, state, airport code or country in the field below. Weather by E-mail: Forecast storm alerts. Weather E-Mail Alert Sign Up »

Next 12 Hours

Forecast data from the National Digital Forecast Database.

5 Day Forecast

• Wednesday
• 
• High: 84 °
• Low: 57 °
• Partly Cloudy

• Thursday
• 
• High: 86 °
• Low: 61 °
• Partly Cloudy

• Friday
• 
• High: 86 °
• Low: 59 °
• Partly Cloudy

• Saturday
• 
• High: 81 °
• Low: 59 °
• Clear

• Sunday
• 
• High: 82 °
• Low: 55 °
• Partly Cloudy

Area forecast discussion...updated 
National Weather Service Huntsville Alabama 
626 am CDT Wednesday may 16 2012 


Update... 
for 12z tafs 


&& 


Discussion... 
/issued 301 am CDT Wednesday may 16 2012/ 
a fairly quiet but complex weather pattern developing over the next 
few days across central North America. An amplified ridge axis 
extends northward over the northern rockies of Canada with a 
meandering weak cutoff low dropping across central Nevada. In the 
meantime, an elongated/positively tilted trough axis digging south 
over the western Gulf states extends eastward towards the Carolinas. 
To the north of this elongated trough is a longwave trough axis 
extending from the Great Lakes northward into Ontario. 


The elongated trough has dived far enough south to keep the Tennessee 
Valley dry and warm, as daytime highs rise into the low to middle 80s. 
Cirrus associated with the elongated trough is expected to build 
northward across mainly the NE portions of the County Warning Area. This will likely 
keep temperatures over that area 'cooler' than the rest of the forecast 
area. Model products are then indicating a shortwave trough (with an 
accompanying weak cold front) dropping southward from the prevailing 
westerlies for Thursday. 


Though moisture return continues to be a question mark, retained 
isolated (mainly afternoon) thunderstorms in the forecast for 
Thursday and Friday over NE Alabama/portions of S middle Tennessee. Inverted v 
profiles are indicating the possibility of gusty winds due to 
microbursts as the main threat. Forecast confidence is low to average 
for thunderstorms. 


As this trough drops south, the European model (ecmwf)/GFS/Canadian models are 
indicating the development of a Rex block pattern over the eastern 
Seaboard (or just off shore) with remnant energy from the elongated 
trough retrograding westward underneath the building amplified ridge 
over eastern North America. Though the cyclonic circulation 
underneath the anticyclone appears to be of a weak nature, have kept 
isolated thunderstorms in the forecast for Sunday afternoon. This is 
also due to moisture pooling south of the Tennessee River, especially over 
central Alabama. Saturday looks too dry for thunderstorm activity. Temperatures 
are expected to rise into the low to middle 80s with overnight lows 
mainly in the upper 50s to low 60s through the period. 


The remaining forecast challenge is another shortwave trough diving 
southeast from the northern plains into the the MS/Ohio River valleys 
by Monday. The accompanying weak surface cold front appears to stall 
over the MS and Ohio rivers by Tuesday as the prevailing westerlies 
shift north, effectively shearing the shortwave trough as it drifts 
south. Thus, have pulled thunderstorms from forecast on Monday and 
instead kept them from Tuesday afternoon Onward. The weak nature of 
the shortwave trough keeps ME from placing much confidence in this 
part of the forecast. 


Sl.77 


&& 


Aviation... 
for 12z tafs...patchy MVFR/IFR fog conditions are expected to clear by 
around 14z across the area. Expect VFR conditions through much of the 
remaining forecast period. Have added in MVFR fog conditions from 09z 
through the end of the forecast period for both mean sea level and hsv for 
expected fog development. 


Tt 


&& 


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


$$ 


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