Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service Paducah Kentucky
355 am CDT Wednesday Apr 1 2015

Short term...(today through Friday night)
issued at 355 am CDT Wednesday Apr 1 2015

Things will get rather busy in the weather department over the
next few days. A persistent southwest flow aloft will gradually
raise moisture and instability levels in advance of a cold front
and low pressure system that will cross our region on Friday. The
models have come into better agreement on the timing and location
of heavy rainfall/severe weather potential over the next few

First things first... today will be another warm and mainly dry
day. Southeast surface winds will keep the low levels quite dry in
most areas. Later today...the leading edge of elevated moisture
and instability will begin to work its way into southeast
Missouri. Will maintain slight chance probability of precipitation in the kpof area this
afternoon. Nearly all guidance was too cool the
forecast was trended toward the warm side of guidance today. Highs
should be in the 70s again today...but just a little cooler than
Tuesday since 850 mb temperatures are a shade cooler.

During tonight...the low levels will moisten up quickly as 850 mb
winds become southwest and increase to 40 knots or so. Scattered
showers and storms appear increasingly likely given the low level
warm moist advection ahead of a 500 mb shortwave moving northeast
from the Southern Plains. Most guidance shows some light quantitative precipitation forecast
across our region overnight.

On Thursday...showers and storms will continue to increase ahead
of a cold front that will reach central Missouri by evening.
However...the majority of the activity should hold off until
Thursday night...when the front will reach southern Illinois and
southeast Missouri. Probability of precipitation will remain categorical for Thursday
night...and the mention of heavy rainfall will continue.

On Friday...a surface low pressure center will ride northeast
along the front...passing through the lower Ohio Valley in the
afternoon. This low will prolong the duration of heavy rainfall
potential into the day Friday. In addition...severe weather
potential will exist in the warm sector...which will be along and
southeast of the Ohio River.

The storm total rainfall amounts have trended upward in both model
guidance and wpc guidance. Given the slow movement of the frontal
boundary...high precipitation water values near 1.5 inches...and a low
level jet around 40 knots...forecast quantitative precipitation forecast will be nudged upward in
line with guidance. Will forecast storm totals from 1.5 to 2.5
inches...which is still a little below the 00z GFS and European model (ecmwf)
totals. The 00z wpc excessive rainfall potential outlook indicates
a moderate risk for our will issue a flood potential
outlook /esf/.

As far as severe potential...thermodynamics will not be especially
favorable due to widespread clouds and convection. Some isolated
severe storms are possible. The highest potential appears to be
early Thursday evening prior to nocturnal cooling of the boundary
layer...and again Friday in the warm sector of the low.

Clearing and colder conditions are expected Friday night. Some
frost appears likely as lows will be in the middle 30s. Winds will
become light toward daybreak.

Long term...(saturday through tuesday)
issued at 355 am CDT Wednesday Apr 1 2015

Medium confidence in the long term due to minor model differences.

The long term period starts off with surface high pressure
overspreading the region in the wake of a frontal passage on Friday.
The high pressure will keep the region dry through Sunday.

Precipitation chances make their way back into the forecast starting
Sunday night as sustained southerly lower tropospheric flow brings
deep layer moisture back into the region combined with periodic
impulses of upper level energy moving through the zonal flow and a
slow moving frontal boundary approaching from the plains. Chances
for showers and thunderstorms will slowly increase through the end
of the long term period as the frontal boundary draws closer with
the highest probabilities expected on Tuesday.

Temperatures are expected to remain near normal through the long


issued at 1101 PM CDT Tuesday Mar 31 2015

With the 06z Wednesday forecast issuance...VFR conditions will
dominate with a gradual transition of winds from northeast to
southeast with time. Unrestricted ceilings and visibities will
remain through nearly all the forecast period with a cirrus deck
moving in after 00z Thursday over kcgi and kpah ahead of the next


issued at 355 am CDT Wednesday Apr 1 2015

March was a wild month across our region. At Paducah...there was a
difference of 85 degrees from the lowest to highest temperature of the
month. The low of minus 6 occurred on March 6...and the high of 79
occurred on March 31. The low of minus 6 was the coldest temperature on
record in the month of March. The snowfall at Paducah was 12.1
inches...which all occurred in one storm on March 4 and 5. This
was the third biggest snowstorm on record at Paducah. It also made
March the second snowiest March on record at Paducah. The monthly
precipitation was 8.73 inches at Paducah...making this the 6th
wettest March on record. Even though the month was far from
normal...the monthly temperature averaged out surprisingly close
to normal...about 2.7 degrees below normal.


Pah watches/warnings/advisories...



National Weather Service Glossary of Abbreviations