Scientific Forecaster Discussion
fxus62 kjax 271930
Area forecast discussion
National Weather Service Jacksonville Florida
330 PM EDT Thu Jul 27 2017
..unusual late July cold front to continue wet conditions this
weekend into next week...
Near term /through Friday/...
A mid level low, with a weak surface low under it will lift
northeast of the region Friday afternoon. Convection will continue
this afternoon into evening, with this activity dissipating after
sunset. Cloud cover will persist though into the overnight. With
diurnal heating, isolated to scattered convection will initiate
later Friday morning, and continue into the afternoon.
Temperatures will be above normal this period.
Short term /Friday night through Sunday/...
Models still on track with pushing a rather unusually strong cold
front for late July through the southeast U.S. And into southeast Georgia/NE Florida in
this period. Forecast remains on track for numerous showers and
storms to break out along and ahead of this front across southeast Georgia
Saturday morning and NE Florida Saturday afternoon/evening before the
front slows down and stalls across north central Florida on
Sunday. There is a marginal threat of severe storms expected as
this feature moves through the region with strong/damaging winds
the main threat but it still appears as though a pocket of warm
mid level air with 500mb temps in the -4c to -6c range will limit
the severe weather threat by limiting steep lapse rates. Also due
to the saturated ground conditions, locally heavy rainfall will be
a secondary threat as the front slows down across the region with
widespread 1 to 3 inch rainfall totals expected through Sunday
and localized totals up to 4 to 6 inches possible. Highest totals
with this event appear to be across NE Florida where the front slows
down on Sat night and Sunday. Lows will generally be in the 70s
through the period, but highs on Saturday will reach into the
lower to middle 90s ahead of the front across NE Florida with heat
indices around 105 degrees, while southeast Georgia should top out closer to
90 degrees with the earlier start to convection. Likely reversed
situation on Sunday as clouds/convection with frontal boundary
across NE Florida will hold Max temps into the mid/upper 80s there
while southeast Georgia areas should reach to around 90 degrees.
Long term /Monday through Thursday/...
Rather wet period expected as stalled/washed out frontal boundary
across north central Florida early in the week with deep tropical
moisture will slowly lift back northward by the middle of the
week. Overall expect numerous showers and storms mainly diurnal in
nature to contain the main threat of heavy rainfall each afternoon
and evening. Temps will remain below normal as highs only reach
into the middle/upper 80s each day with the abundant cloud cover.
Additional rainfall totals of 2 to 4 inches are possible next
week with the highest totals across NE Florida and coastal areas as
onshore winds early in the week may help develop a few stationary
convergent rainfall bands.
convection will continue across the region this afternoon into this
evening with restrictions expected. Convection will dissipate after
sunset, then initiate once again mid morning Friday. Patchy fog
could lead to restrictions overnight into Friday morning.
an area of low pressure will lift northeast of the region on Friday.
A cold front will drop south into area waters Friday night. This
front will slowly sink south across area waters through Sunday
night. The boundary should be just south of the region early next
week as high builds to the north.
Rip currents: low risk through Friday.
despite all of the expected rainfall over the next week with
widespread 7 day totals of 3 to 5 inches with locally higher
amounts, still way too early to determine the need or extent for
any Flood Watch. Also the diurnal nature for most of the
convection will allow for long enough periods of time in between
locally heavy rainfall. The best chances for any flood watches
will be Sunday into Monday along the coastal areas and across NE
Florida where the stalled front will be, along with any possible
stationary convergent rain bands at the coast.
Preliminary point temps/pops...
amg 73 92 75 90 / 20 30 20 70
ssi 75 91 78 90 / 40 20 10 70
jax 74 93 76 93 / 50 20 10 70
sgj 76 94 77 93 / 50 30 10 40
gnv 74 92 75 92 / 20 20 10 30
ocf 74 92 75 92 / 20 20 10 30