January Thunder Preludes Cool End To The Week

Images: These images depict 'actuals' at 7AM, during which time we still had light rain across Central Florida with embedded thunder. We see the cold front pushing slowly down the peninsula which has since cleared Cape Canaveral as of 9AM when the temperature went from 64F to 59F on the porch here.

RECAP: The weather radio went off at 7AM as large spatters of rain bounced off the bedroom window and thunder had just rolled overhead less than a minute earlier. It was for a Special Marine warning in regards to wind gusts. A few other alerts have since been sounded for the same reason. This was expected to be possible (the stronger wind gusts) as written yesterday with the stronger mid-level winds racing overhead. For example (as issued by the National Weather Service (NWS)):

LZ053-054-058-059-061330-
INDIAN RIVER-OKEECHOBEE-OSCEOLA-ST. LUCIE-
729 AM EST THU JAN 6 2011

...A SIGNIFICANT WEATHER ADVISORY IS IN EFFECT FOR STRONG WIND GUSTS BETWEEN 45 AND 55 MPH OVER INDIAN RIVER COUNTY...OKEECHOBEE COUNTY...SOUTHERN OSCEOLA COUNTY...ST. LUCIE COUNTY...* UNTIL 830 AM EST.

TODAY: Story of the day is simply gradually improving weather conditions for Central Florida from North to South, with deteriorating conditions over South Florida during the late morning and into the afternoon as the front pushes southward toward that area. They are in for more of the same as what Central Florida experienced during the wee hours of this first Thursday in January.

Satellite animation/timing estimates to my best guess shows the most significant clearing line of clouds to be along SR528 between 11:30AM-12:30pm. However, the driest of air is still well to the north. With this in mind, hard to discount that with the initial cloud breaks occurring at or near peak sunshine time, any heating on the still somewhat moist air mass will result in re-development of stratocumulus clouds in scattered to maybe even broken fashion until sunset over the immediate Central Florida area, much more assuredly only widely scattered north of I-4 to nearly clear.

As noted yesterday, believed the warmest time of day would be before the front passed, and that temperatures would hold near steady from the point at which the rain hit overnight. The temperature has fallen since sunrise with the FROPA (frontal passage) by 3-5F degrees (which just occurred at 8:50AM), and with clearing to commence during the time the sun is near its peak azimuth this leaves little time for heat to accumulate. With expected strength of afternoon west to WNW winds this afternoon mixing in the lowest levels could regenerate more clouds and prevent a good warm up, so shooting for a high in the low-mid 60s this afternoon with a breezy WNW wind. But the rain is over now north of 520.

TONIGHT: Drier air and a more NW wind component will usher in a temperature drop beginning at sunset as skies rapidly start to clear in accordance with the drier air. Temperatures will fall throughout the night with a continued NW wind all night bringing them to just above 40F at sunrise with a nearly clear sky. In short, it'll be chilly Friday morning with wind chills being a big factor as well.

FRIDAY: Below normal temperature day in store with the low just above 40F and a high right near 60-62F along a Cape Canaveral to South Tampa Bay line, but warmer the further south one goes. From North Brevard to North Tampa Bay the temperature might only be in the mid-upper 50s tomorrow with winds beginning to back toward the west but remaining elevated until late day.

SATURDAY: Another very cool day to start with mid-40s wide spread, but winds decrease. Highs in the low-mid 60s for the most part across the dead center line from west to east across the state and warmer south into the mid-upper 60s with low 70s restricted to the East Coast from near West Palm to Miami and the Keys. Winds continuing generally from the west but of less strength.

SUNDAY: Another cool start similar to Saturday but warmer in the afternoon by about 5 degrees. The GFS is still quick to swing the winds around to onshore overnight which would mean significantly warmer air east of I-95 or US1 (mid-50s) by sunrise. Didn't wait to see the morning model run to make this post to see if it is still latching on to this early onset of an onshore wind shift, but no rains. Additionally, either way (whether the wind shifts by morning or not), the afternoon will again be even warmer than that from Saturday afternoon. Mainly in the upper 60s with 70s further south.

By late in the day our next storm system will have already taken shape in the far Western Gulf off the Texas Coast. This system will move rapidly east along the northern Gulf during the day as it approaches the Florida Panhandle coast line Monday morning. Very mild weather overnight Sunday into Monday ahead of this system. It appears the low pressure system will take a similar track as this last one (namely, from west to east and exiting off the Florida East coast close to, or just north of Jacksonville).

On the weather map, the cold front that will be lying dormant south of the Florida Keys could very well return 'as a warm front' Sunday night into Central Florida as heights rise ahead of the surface and mid-level low pressure area. The system will provide another quick shot of rain, but a somewhat 'active event' comparable to this last system does not seem to be in the making. The atmosphere probably won't have had enough time to recover from the air mass that is still moving in today and tonight. This will definitely need to be watched though since it's not assured this will be the case. At this point, it does not look as if we will see the statewide temperature warm up as was experienced prior to the system of today, so instability will be lacking even more. Intensity of the low, warm air advection ahead of it, and mid-level winds all will require close scrutiny as the time approaches, considering none of the above has yet to even evolve.

MONDAY: Probably cloudy all day with temperatures holding steady in the upper 60s with shot of rain. Naturally turning a bit colder once again once the front passes. Hate to say it, but the trend going into the 2nd and 3rd week of January is for each successive frontal passage to be colder than the previous one. With the said, the system next week will provide cold temperatures in the 30s by Tuesday/Wednesday. Just how low into the 30s is beyond predictability. It also appears that it will ride closer to the U.S. east coast bringing a big snow event for the folks in the Northeast States by next Tuesday/Wednesday.

PRELUDE: 3rd Week of January. Winter could hold 'true to form' with the coldest nation wide event to occur from the 17th - 23rd. This falls right in line from what we learned in school, that being the coldest time of the year occurs 1 month after the sun has reached its lowest point (December 21st). The pattern looks very active with much of the country being in the cold air for a prolonged time. Central/South Florida, the Gulf Coast, and California escape the worst of it though...which would be typical. But I DO NOT like what the GFS is showing around the 20th for Florida. Now really, snow?!! Maybe Mother Nature has been reading up.

Naturally, this is well beyond the scope of reason, but the general trend is for a persistent upper level gyre to remain over the Great Lakes to James Bay (as has already begun). Would not want to live north of the Mason-Dixon Line that's for sure beginning about now.