Scientific Forecaster Discussion
Area forecast discussion...updated
National Weather Service Memphis Tennessee
1241 PM CDT Thursday Jul 30 2015
Updated to include the 18z aviation discussion below.
Discussion... /issued 334 am CDT Thursday Jul 30 2015/
Cooler and drier conditions are the story through the next few
days as many enjoy a break from the oppressive heat...
Currently aloft...500 mb ridging was still in place across much of
the southern US with a departing upper level low across central
Canada. At the surface...a frontal boundary was moving south
through portions of northern Mississippi. Heights were rising
across much of the midsouth.
For Thursday...a much more pleasant day is expected with upstream
observation showing dewpoints in the 50s across much of Iowa...increasing
into the low and middle 60s across Missouri. This airmass will
continue to advect into the midsouth on Thursday which will feel
exceptional after experiencing several days of dewpoints in the
upper 70s. Temperatures will rise into the upper 80s to lower 90s
with the warmest readings south across northern Mississippi. Given
the dry nature of the airmass...lows were decreased slightly for
Thursday night with middle and upper 60s to near 70 expected.
Friday through the weekend...a slow warming trend will develop but
it will take some time for moisture to advect back into the
region. Even with warmer temperatures...relatively low dewpoints
will keep heat indices very much in check. This period is also
expected to be dry so a very nice weekend is in the offing.
In the long term...a blocking-type pattern develops in the upper
levels with a trough-ridge-trough feature taking hold by middle to
late next week. This solution is agreed upon by both the Euro and
GFS...and similarly in gefs guidance. If this holds true...warmer
temperatures can be expected with periodic tstorm chances as
shortwaves dive southeast around the eastern Continental U.S. Trough.
18z taf cycle (30/18z-31/18z)
VFR conditions will occur through the period. Winds today NE 10-13
kts with gusts 18-20 kts. Winds tonight NE 3-7 kts. Winds Friday
morning becoming NE 6-10 kts.