"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".

Tuesday, February 15, 2011

An End To Lows Below 50F Begins

Image: Forecast for 9AM this Tuesday morning shows high pressure building SE into the Mid Atlantic ocean through the rest of the week as noted with the black arrow. Leading edge of the influence of this high pressure area is highlighted by a 'back door' cold front as shown at 9AM to be crossing the Jacksonville, FL area pressing SSW through late morning into the early afternoon.

TODAY: As noted above, a 'back door' type cool frontal boundary will cross much of North and North Central Florida today, then slow down and stop somewhere across Central portions of South Central Florida, never reaching South Florida in the short-term. NW winds this morning will begin to veer toward north late-morning and shift to NNE-NE and pick up a bit this afternoon following passage of the boundary across the NE quadrant of the state, mostly notably along the east coast from near Satellite Beach north to St. Augustine. Otherwise, few clouds will be noted.

The benefit of this boundary in passing will be higher dew point temperatures (more moisture in the low levels) advecting from east to west across North and Central Florida, most notably after 1pm today and beyond. Dew points in the 50s will eventually advect in across much of the area progressively from NE through SW beginning shortly after noon time through this evening and into Wednesday as high pressure moves off the Mid-Atlantic coast and begins to settle a bit further south over the Western Atlantic waters well off shore the state by several hundred miles.

TEMPERATURES TODAY: The only fly in the ointment for today will be the afternoon high temperature from near St. Augustine south to Satellite Beach, especially (and in a more focused area) from near Ormond Beach to Port Canaveral to just north of Patrick AFB) east of US1, and especially along A1A. As noted, winds between 11am - 1pm will veer to a more N to NE component approximately around this time frame and usher in higher dew point temperatures.

However, these winds will also be blowing across sea surface temperatures measured yesterday off Daytona Beach that were 55F. Ugh. The wind shift will be most notable during peak heating, especially around 2-3 pm through the remainder of the afternoon as full sunshine heats the atmosphere and stronger winds at 2000ft mix to the surface (ground level). These winds will advect (or "push in") the very cool air to those folks, mostly affecting residents along and east of A1A north of Cocoa Beach. But to what 'degree'? The 'degree' I'm thinking of would result in a high temperature in the low-mid 60s, perhaps falling into the upper 50s between 5-6pm as the sun gets low.

I've noticed on satellite based sea surface temperature estimates that south of Port Canaveral (and as measured off of Cocoa Beach Pier) that water temperatures there are 60F and above (warmer the further south one gets). But again, as noted, from north of Port Canaveral waters were 55F. The warmest near shore waters are from Ft. Pierce and south where the Gulf Stream is much closer to shore.

So in essence, the gist of my post today hopefully reflects an interest in seeing just how cool it will be this afternoon, even with a warm up earlier before noon time. Of interest as well, is in noting that the official forecast is reflecting highs in the upper 60s on the coast, but be advised, yesterday afternoon while most areas were 70F degrees...the readings on the KSC mesonet along the eastern points of the Cape just north and east of the Port Entrance at Port Canaveral were 59F with just a light 5mph NE wind at that time.

So you see, with a stronger NNE-NE wind (12-20mph just offshore) later today, why my 'interest' is perked. Just to be safe, if you're planning to head to Playalinda Beach, Ormond Beach, Daytona, or The Port from inland areas...I'd bring a jacket.

TONIGHT: High pressure will move well offshore the Mid-Atlantic Coast and sink a bit south, whereas another area of high pressure will build northward from the Gulf of Mexico. Between these two entities at play, surface winds overnight will veer more from northeast to from due East and blow off 60F degree ocean waters from the Port and South. Therefore, there will be very little temperature variation between the 'post - 6pm' temperature and that which will be felt Wednesday morning along A1A, with a low in the upper 50s. Inland temperatures will fall into the -mid 50s, coolest over the west side of the state...perhaps even toward Sarastoa where the dewpoints will be last to warm and they'll have an overnight land breeze.

WEDNESDAY: Prolonged onshore flow will have lifted low level atmospheric moisture levels to the level ample enough for cloud generation. As such, believe that overnight (tonight after midnight) some stratocumulus clouds will be begin to move in, providing further reason for overnight lows to remain warmer in the absence of any radiational cooling/dry air/clear sky conditions/calm winds. As noted in the post on Sunday, and will repeat in the post this morning, I will throw in a "silent 10%" chance of a light rain/sprinkle from shortly before sunrise through Wednesday from Sebastian to St. Augustine...silent because any 'rain' , per se, wouldn't hardly be enough to wet the ground.

The majority of Wednesday appears will be party cloudy, and at times, mostly cloudy with the sun still peaking out in the absence of anything but low, stratocumulus clouds. As mentioned, winds on Wednesday will be almost due east, so expect highs to be in the upper 60s (between 67-69F) east of State Round 3 up and down the coast of Central and South Central Florida, with low-mid 70s west of I95 from Central Brevard south to Miami (and the Keys). Again, though, the fly in the ointment for coastal North Brevard and Volusia County will be the extent of clouds combined with the wind (lighter tomorrow than this afternoon) along A1A, over Volusia and Flagler County...and north of Canaveral Air Force Station. Could still be flirting with low-mid 60s there. South Florida, no problem in the never ending non-changing weather pattern. Very pleasant there, but with some clouds.

THURSDAY-FRIDAY: Surface winds will begin to veer a bit more toward the ESE-SE and remain very light. Overnight lows along the coast in the upper 50s, approaching 60F on Friday along A1A. Cooler west of A1A with lows in the mid-upper 50s. What is left of the backdoor boundary could shift further south by Thursday due to a secondary resurgence of high pressure to shift the chance of light rain spits further south toward West Palm to Miami on Thursday. Otherwise, very pleasant with inland high temperatures in the Mid-upper 70s, with the coast hovering closer to 68F....must say, I want to say 70F because it sounds good, but don't think its going to happen along A1A north of Patrick AFB.

WEEKEND: Looks like another back door boundary will come through sometime on Saturday. This has been shown by the GFS to occur for several days, even while it was showing this initial one today, so this is no surprise. The net affect with this boundary, initially, will be to back surface winds to NE for a brief time over North Central and Northeast Florida...with a return to conditions similar to what will occur later this afternoon. However, this time the high pressure will rapidly settle in further south with return surface winds from more of a southeasterly component.

Meanwhile, while this is all going on late this week and into the weekend mid-upper level high pressure will be building NEward from Southern Mexico and into the Central Gulf. Remember my writing several days ago that we would be under the influence of high pressure for quite some time after we cleared of the rain/ cloud producing cold front early last week? And it would be the 'source' of the high pressure that will make the world of difference in our local weather?

Well, this high pressure source from Mexico will be the clincher going into early next week. That is to say, instead of messing with modified North Pacific/Continental high pressure like we will be through the remainder of this week, we'll be messing with High Pressure from the South/Central waters of the Pacific at the surface and aloft combined with those of the Gulf of Mexico.

Net affect, no matter how one looks at it, warming in the mid-levels will bring abundant sunshine with partly cloudy skies...highs in the upper 70s by later this week and into next week continue...with some low 80s in the far interior portions of South Central and South Florida. Overnight lows in the low 60s coastal, mid-upper 50s inland.

Finally, even our Tarot Card Dealing Crystal Magic Ouija Eight Ball is not showing any cold fronts to impact Central of South Florida through the 1st of March and beyond. Does this mean we'll not see another cold front the rest of calendar Winter? No. Some cool downs could still occur. And the chances of severe weather due to frontal systems/low pressure still remains through mid-late March. Remember now, we had Severe Weather Awareness Week when it was (last week) for a reason, so that folks woiuld be prepared, reminded, and forewarned of the upcoming periods of potentially active (or severely inactive) weather extremes.

In some posts the remainder of the week, I'm going to try to remember to include some examples of what has happened in the past over Florida between Mid-February through March. You might be surprised to see what has happened in the past during this time frame, considering what the weather outlook is showing for the next 10 -14 days. But for a hint, don't forget the "Super Storm" and the worst Central Florida Tornado Outbreak in Florida History in the 1990s.

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