"But seeing they could not See; hearing they could not Hear"
“The views expressed herein are those of the author and do not necessarily represent those of the National Weather Service or affiliate/related organizations. Please consult .gov sites for official information”

"From its chamber comes the whirlwind, and cold from the scattering winds." - Job 37:9.

"The wind blows to the south and turns to the north; round and round it goes, ever returning on its course".

Wednesday, January 11, 2012

Gusty Winds Today, Rain Good Bet, A Strong Storm Possible

Mean Sea Level Pressure (MSLP) Lines and 10 Meter Winds AGL in Knots (Above Ground Level) per the Melbourne, FL National Weather Service (NWS) Website (see link in graphic). Front is shown in Gulf of Mexico. Expecting stronger activity today , if any, to be south of the red line. Prefrontal trough to be enhanced by late morning toward noon time with higher sun angle, although cloudy skies will prevail throughout the day offsetting  heating.

The above image shows where some boundaries at the surface exist. The satellite image shows what the sky looks like from above the clouds we see looking down toward earth.

CLOUDY skies can be see from space over Florida. Storms
are embedded within these clouds, mainly off Southwest Florida, with another small line becoming organized  about 60 miles west of Cedar Key near the lower Big Bend. The 'cold front' really is not much of a cold front seeing how it originated over the SW United States. The colder air is behind another front to come early Friday.

TODAY: Rain chance increases across the state today, although anticipate that not many areas will see the heavier rains. In fact, most areas will only experience light rainfall. A trace of rain fell in Canaveral near daybreak along with a "Red Sky at Sunrise". There is an old adage, "Red Sky in Morning, Sailor Take Warning".  Rain chances are shown by most of the model guidance to pick up late morning from west to east as daytime heating (albeit weak due to cloud cover) increases mid-level lapses rates (change in temperatures with height) to only a small degree. Otherwise, wind energy associated with the mid-upper level troughs which are propagating the surface front eastward will increase across Central and South Florida after Twelve Noon. At that time is when rainfall coverage could increase. Any storms will be embedded within the cloud cover, and will not be easily discernible upon their approach until very close to any one (your) location. Temperatures to remain in the low-mid 70Fs, possibly toward upper 70Fs far East Coast south of Brevard.

STORM CHANCES: As of this writing, a small cluster of storms with some lightning has taken shape well west of Cedar Key, FL which is located generally WSW of Gainesville, FL along the west coast. The biggest cluster of storms is well west of SW Florida in the Gulf. This cluster is closely linked to the warm Gulf waters of the Loop Current. It is thought by all guidance they will never make it to shore once they begin to depart those warm waters. So far, loops of radar and lightning animation seem to be verifying this line of thinking, but can never say never toward South Florida. For now though, the trend of several days has shown little activity over South Florida with this system, and early morning model runs have not changed along those lines.

Better chance appears now to be South of I-4 and north of a line running from near Sarasota to Vero Beach as was surmised yesterday. A few graphics are included below with descriptors.

Helicity is a measure of corkscrewing winds in the horizontal. The red shows higher helicity. The higher this value, the greater potential for lifting mechanisms in the atmosphere to act upon any shower or storm that can manifest in the generally unfavorable environment today. But one can never be sure in cases similar to those of today. In the past, a strong toward severe storm or two has managed to manifest regardless of preconceived notions. Believe the best chance of any such activity today over land will occur between the lavender lines, especially Brevard County. 

This above plot is as close to 'actual' as one can get. NOW, we can look at the Rapid Updated Cycle (RUC) model forecast plot for this afternoon around 3pm. This is  showing the Energy Helicity Index at the lowest atmospheric levels. The Green Shows at least 'something worth noting'. This value combines both helicity and Convective Available Potential Energy (CAPE) in the atmosphere...(long story).
01KM EHI  (Energy Helicity Index) per RUC. Note where the green is located. By the next hour in this run of the model, these values are even higher but have moved offshore Brevard, Southern Volusia, and Indian River County. Prior hours to this time frame show little. These are coincident with during and just after peak heating, no coincidence. Note another peak in green toward SW Florida. 

 ...For today, cloudy and breezy. Guidance shows winds of 40 knots just above the surface, so it is possible Small Craft Advisories and Lake wind advisories could be needed after 11AM toward late afternoon as the prefrontal trough and front cross the state. Guidance also shows winds could remain elevated to breezy well after dark. Winds from the South to SSW becoming SW-WSW at 14-22mph with gusts toward 32mph near any showers or possible thunder storms. The strongest wind gusts in storms should they be able to manifest COULD top 55mph, but coverage of such activity will be very isolated and therefore the Storm Prediction Center is no longer outlooking Florida for severe weather. The more favorable location is the Carolinas closer to the parent surface low pressure center.

Better chances for strong activity almost anywhere along the west coast toward West Central and SW Coast, as well east East Central. Brevard/Osceola, Eastern Orange, and Indian River Counties seem to have a better chance of stronger winds and a brief but heavy down pour, not to discount Northern Palm Beach and Martin Counties as well. Cloud to ground lightning is possible as well, but very isolated. Expect most lightning to be  in-cloud or cloud to cloud. 

It has not rained heavily in quite some time for most areas, so it is a good point to be made that roads could become slick easily today, and will be traversed during rush hour while still wet. The biggest threat today will be the roads, although some gusty winds and who knows, maybe a brief 'spin-up' like tornado toward East Central, but definitely not hanging any hats on that hook.

BEYOND: Front to clear the state after dark, and become draped out across the Florida Straits close to or just south of the Keys until the true COLD FRONT crosses the state overnight Thursday night and very early Friday. 

COLD AIR ADVECTION ALL DAY FRIDAY..meaning, cold air filtering in on NW winds even during peak heating. Breezy on Friday and cold, becoming cloudy as well due to the potential of fairly thick altostratus and cirrostratus sun. Hopefully, this will not be the case, but if so, could be highs Central and North will never breach the lower 50Fs, warming into the lower to mid 60Fs South Florida.

will be the potential real weather maker for rain related activity, although showers can accompany the actual front in blue as well. Partly cloudy on Thursday with increasing clouds late as the next front approaches

 THURSDAY OVERNIGHT: Jet  streak of 140 kts winds aloft will be departing the SE States placing Florida in the left  exit region (right rear quadrant)..this generates lifting in the upper levels and could induce cloud coverage during the time of cold air advection.
A lethal combination!! for those not favoring cold weather.

FRIDAY - SUNDAY: Much like those last days that were cold. Winds become light with some sunnier skies but remaining very cool during daylight hours through Saturday and even Sunday to of less a degree. ..but morning lows to not appear will reach freezing, and even frost might be hard to come by due to light winds.

MONDAY: Cool start and then rebound. It still appears another stormy system will be on the horizon around week three of January, but this system now on our door step and the cold air to follow over the weekend and Friday might just be the end of the worst in the temperature department. Just Maybe.

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