Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
204 PM EST Sat Feb 14 2026
Day 1
Valid 16Z Sat Feb 14 2026 - 12Z Sun Feb 15 2026
...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM NORTHEAST
TEXAS TO THE MID-SOUTH...
1600Z Update...
Based on the new 12Z HREF guidance and recent HRRR solutions along
with satellite and radar trends, the Slight Risk area has been
pulled southward a bit into northeast TX, mainly from the DFW metro
area eastward to the Arklatex. This will accommodate concerns for
at least some brief/episodic convective training concerns as
convection grows upscale in an organized fashion out ahead of
strong shortwave energy/height falls ejecting east across the
southern Plains and Lower MS Vallety region. Increasing boundary
layer instability and a strengthening of thew low-level jet should
favor increasing rainfall rates capable of reaching 1 to 2
inches/hour, and with some training potential. Localized swaths of
3 to 4+ inches may occur. Since we are likely to have basically a
QLCS evolution going into tonight across the South, the Marginl
Risk area has also been extended southward to the Gulf Coast.
Overall, most areas should see any flash flooding concerns be
isolated to scattered, and mainly for urban areas.
Orrison
Previous discussion...
A positively tilted upper trough will pivot across the Southern
Plains, while a low pressure system develops at the surface today.
Mid-level diffluence will shed lobes of vorticity over parts of
the Southern/Central Plains and Lower/Middle Mississippi Valley,
providing ample forcing for convection to develop. Thus, showers
and thunderstorms are likely to increase in coverage this afternoon
starting over north-central Texas, into central Oklahoma and
spreading eastward into the Lower Mississippi Valley tonight. The
associated surface wave should strengthen into a rather anomalous
mid-latitude cyclone by tonight, which is when a line of convection
may initiate over east Texas and begin to propagate east across
the central Gulf Coast.
Instability will be most robust (250-750 J/Kg) over east Texas,
southern Arkansas and Louisiana through tonight. 1-2" PWATs will be
2-3 stndv above average and could produce 0.25"-0.75"/hr rates
with higher rates possible within linear convective bands moving
through east Texas and within any potential training/backbuilding
convection that occurs along a surface front draped over Arkansas.
Guidance is hinting at potential for slow moving cells to generate
an isolated flash flood threat over portions of Missouri this
afternoon.
Kebede
Day 2
Valid 12Z Sun Feb 15 2026 - 12Z Mon Feb 16 2026
...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE MID-ATLANTIC, OHIO/TENNESSEE VALLEYS, AND SOUTHEAST, AND
CENTRAL CALIFORNIA...
...21Z Outlook Update...
The ongoing outlook is generally on track although a few changes
were made across Tennessee/Kentucky and across central California
coastal areas. At the beginning of the period, a deformation zone
should set up pretty close to the Kentucky/Tennessee border region
and spread a prolonged period of moderate to heavy rainfall across
those areas. 1-2.5 inches of total rainfall is expected from 12Z
Sun through 00Z Mon. These rainfall totals should gradually create
sensitive ground conditions and result in at least minor runoff
issues in a few spots. The Marginal Risk has been expanded westward
into southern Kentucky and middle Tennessee as a result.
Across California, models depict a frontal band of convection
developing over the central CA coast before gradually shifting
southward during the 00Z-12Z Monday timeframe. Areas of 0.5-1.5
inch rainfall totals are expected, and these totals could fall in
1) a short amount of time and 2) across urban/sensitive ground
conditions. Areas of flash flooding could result.
The remainder of the outlook is on track with no changes needed.
See the previous outlook below for more details.
Cook
...Previous discussion...
The marginal risk area from yesterday's issuance remains mostly
the same, with the only change being an expansion northward in
Virginia. The potent low pressure system that will bring heavy
rainfall to the Lower Mississippi Valley today will continue to
spread moderate to heavy rainfall over parts of the Southeast and
Mid-Atlantic on Sunday. The heaviest rainfall is expected to occur
Sunday afternoon into evening in the Southeast, along the same
cold front responsible for potential linear convection over the
central Gulf Coast today.
MLCAPE will be modest at around 250-500 J/Kg, while PWATs hover
between 1-1.75" over the Southeast. Phasing of this southern stream
system with a northern stream one emerging from the Ohio Valley
could enhance precip. coverage over the Mid-Atlantic this afternoon
into tonight.
Kebede
Day 3
Valid 12Z Mon Feb 16 2026 - 12Z Tue Feb 17 2026
...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
CENTRAL AND SOUTHERN CALIFORNIA...
...21Z Outlook Update...
The ongoing forecast is on track. Convection should organize along
a surface front and gradually shift southward across central and
southern California coastal ranges. Favorable low- to mid-level
trajectories exist for substantial upslope/orographic ascent and
local areas of 1.5-3 inch rainfall totals. These rainfall rates are
likely to occur over sensitive areas and varied terrain, resulting
in instances of flash flooding. A Slight Risk area remains in place
to address the threat.
Cook
...Previous Discussion...
A slight risk was introduced, in coordination with local offices,
across parts of the central and southern California Coast. A closed
mid-level low will weaken while shedding lobes of vorticity over
the West Coast on Monday. An upper-level jet streak (100-140 kts)
will gradually increase in intensity throughout the day as it sags
south from central to southern California. A surface wave will
develop and spread rain showers and isolated thunderstorms into the
central to southern coastal ranges below 6500-5000ft Monday
morning and into the early evening.
PWATs in the 0.5"-0.9" range within a relatively buoyant
atmosphere (100-200 J/Kg) and a 30-40 kt low level jet, could
support efficient rain rates especially within any convection that
develops. Burn scars will be especially susceptible to flash
flooding.
Kebede
Day 1 threat area: www.wpc.ncep.noaa.gov/qpf/94epoints.txt
Day 2 threat area: www.wpc.ncep.noaa.gov/qpf/98epoints.txt
Day 3 threat area: www.wpc.ncep.noaa.gov/qpf/99epoints.txt