"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".

Saturday, July 22, 2017

Storms/Shower Risk Today Up and Down the Peninsula - Even the Beaches (?)

Over the Banana River on this date, 2014
TODAY: Same general synoptic situation is at play but with a slight change in the theme as the old one likely played itself out yesterday with the very early onset across SW Florida associated with colder air aloft - that as a 'renegade' upper low had retrograded from the Carolina's the other day toward North Florida and continues west and out of the picture.

New scene today as temps aloft are just a bit warmer  with the low having moved further from the state -   upper level triggers (vorticity) associated with it are likely more removed from the immediate area (as per model guidance).

Otherwise, Cape sounding showed a convective temperature there of 90F which is up a bit from yesterday, and warmer by about 2 degrees at both the 700mb and 500mb levels. Steering is from the southwest but not so strong as to prevent the east coast sea breeze from forming.  

There  is activity up and down the west coast however encroaching on to the beaches in some locations. Chances are if these storms can collapse and send outflows eastward coincident with the west coast sea breeze, that boundary could make good headway toward the east side of the state while the east coast sea breeze makes much slower progress. 

There is some 'cloud cover' across a portion of southeast Florida which 'might' put a crimp in the storm style down there (if any is to be found at all, 'see below') apart from a merger of the Lake Okeechobee/Sea breeze. That area looks like it might escape the storms today, unless the clouds thin out a bit (hard to say for certain).

Otherwise, apart from other questionable potentials ...the 'better bet' (per the blogger only) for mid-late day storms appears to be along I-10 then south along and west of I95 as depicted below.. also activity could 'pop' as the east coast sea breeze forms but suspect it would be rather isolated, at least compared to yesterday's standards.

The region over South Florida (south of Lake Okeechobee) will likely need to wait for the sea breeze collisions later in the day as well; the Miami sounding had a precipitable water value of around 1.72"   (but the moisture was more evenly distributed up and down the column) - and as such, it appears for now a bit iffy for storms down there; on the other-hand, it is thought this area might moisten up a bit later in the day with the peak of activity closer toward the west side.

Overall, suspect the 'better concentration' of storms with at a minimum 'anvil debris rains' at the immediate coast even will be portions of Central (East Central to eastern portions of North Central)..then along a southwest line from near Yeehaw Junction toward Ft Myers.

SUNDAY: Expect less concentration of storm coverage at this time, though upper level winds do not change, moisture availability might. The GFS showed a similar set up as today with a few variations which would be par for the course of things running along in 2-3 day 'cycles' or themes' as the larger scale synoptic scale situation across the country undergoes some subtle changes.

BEYOND: Little variation in the 'winds at the surface and aloft' forecast, with more sensible (observable) changes occurring in regard to where moisture will be ample enough. Guidance is providing varying forecasts regarding this particular variable , making an extended outlook sketchy at best.  However, there is consensus that some definite 'rather dry slots' will impede or pollute parts of Central Florida at times in the upcoming week as well as South Florida; North Florida seems to be the location where a steady increase of moisture is expected into mid and late week. 

Expect there will be days that shower/storm coverage will be significantly hampered in particular regions/areas of the state more so than others, but exactly where cannot be pre-determined at this time. The GFS shows little change, overall (as just described) into the end of the month (for the time being at least)

July 22, 2014 over the Banana River as Viewed from Cape Canaveral

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Friday, July 21, 2017

Larger Rainfall Totals - Heavy Thunderstorms Again - With Some Near Coast

Storm Clouds Loom Over Hickory Tree Road in Osceola County on Thursday.
Vivid Lightning was dead ahead at the time of image
St Cloud in Northern Osceola reported over 2.5" of rain yesterday
TODAY: Looks like a variation of yesterday's theme. KSC sounding came in at around -7.5C at 500mb and a bit cooler at 700Mb at around 7C (from yesterday). With no capping in place and little in dry air up from the surface to 500mb column would except showers to initiate easily once convective triggers are reached by noon time or so (the KSC sounding shows the convective temperature to be 89F for that area), outside of earlier smaller showers that could begin sooner.  There is already plenty of activity across SW Florida progressing slowly eastward.

Low -mid level ridge axis remains suppressed to far South Florida up toward Southern Shore of Okeechobee County today and tomorrow.

As such, steering in the mid-levels is from the WSW at about 10kts but suspect once sea breezes kick in that most storm motion will be dictated by propagation along the sea breezes as they progress inland and then along outflow boundaries / lake breeze mergers until the brew is mixed until there is one big convective mess 'somewhere' over the interior. The slightly better winds aloft today will only lead to further unpredictable storm motions across into areas that haven't already been worked over by earlier storms. The blue area in the image below is a 'guess' of where that might be.  

Biggest hazard again today will be driving in heavy rainfall and the ever present cloud to ground lightning strikes that can occur prior to heavier rainfall onset under billowing cloud tops or even outside of the storms themselves in 'clear air'.

SATURDAY-SUNDAY: For now will clump these two days together as the Song Remains the Same more or less. Only difference might be for a slight decrease in coverage, namely on Sunday, and that steering toward the immediate east coast north of Palm Beach County might increase just a bit; either that or the east coast sea breeze might get pegged closer to the coast if winds at the 925-850mb levels increase more toward 15kts which is being implied as a possibility on both the morning NAM and GFS model runs. Of the two days, Saturday looks to be the day for a Strong Storm potential once again, with decreasing coverage on Sunday.

MONDAY-WEDNESDAY: Main shift from previous thinking is that the ridge axis' remains across South Central toward South Florida for the duration into next week, even into NEXT weekend. That is to say, somewhere across South Central Florida. The pattern seems to favor more and more the east side of the state for mid-late day storms, though there is some drier air that is going to be thrown into the mix. The GFS runs a 'dry slot' across mainly Central or South Central for several days. Inevitably if this is the case, it will mean many areas will remain rain free, but on the other hand some areas along the moisture gradients across South Central and or North Central might see some vigorous updrafts evolve late in the day. 

FAR BEYOND: Just for now and then we can see how things change in the future, the GFS implies this 'drier' period for some areas will remain relatively brief, (maybe 2-4 days) as yet more moisture begins to fill in and steering remains from the WSW-SW. Granted that is too far out in time; just to throw the bait out for now..then we can see how well the models continue to bite on that prospect  in future runs.

TROPICS: Nothing in the tropical realms of concern at this time into the first week of August (at least). Even if something were to form in the Atlantic, given the upcoming pattern :  location of the ridge axis, and winds would not be welcome for a visit to the "Sunshine" State.

Heavy rainfall along SR528 near I95 on Thursday

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Sunday, July 16, 2017

Active July Pattern , Monday-Thursday

Sunday Morning - Cocoa Beach, Florida
TODAY: No changes from previous post of the other day. Pattern change from days of late slowly in progress today most notably will begin for the wee hours Monday morning as surface winds along the east coast (at least north of Palm Beach County) become light offshore (westerly) before day break as opposed to easterly or near calm . Mid-level winds also to shift from light east to west to more  from a southwest component as the mid-level ridge axis drops from Central Florida late today to near Lake Okeechobee  by tomorrow morning (though quite light).

Otherwise, for today moisture to be ample enough though some dry - pockets (like today) might well remain. 

Sea breeze converge appears will be maximized mainly North of "Dead Central" across the Interior from the Suwanee River Basin south into parts of eastern Lake County/ Western Volusia then south-southwestward  toward Central and  eastern Polk county (?) , but over all coverage appears will restricted inland except north of Ormond Beach. Better chances of seeing activity nearer the coast from St Augustine  northward.

Increased moisture was anticipated in previous post for South Florida which was the case, and as a result rain showers were set off  earlier day  ; however, at this stage it appears said activity set off outflow boundaries that 'might' have scoured out large portions off inland South Florida unless those areas can 'recover their loses'    for late day storms (which is always possible).

Not all areas in 'Orange" will see thunder or even rain today; most will be more isolated
except north of I-4 over the interior toward I-10

MONDAY: The GFS and now the NAM as well as other models have shown a curious 'thing' to occur tomorrow over the peninsula taking the form of what appears would be something like a mesoscale, perhaps heat induced surface low pressure circulation centered either near interior North Central or South Central Florida.  All in all, it looks like a thermal trough up and down the spine of the state might evolve, which in some cases results in long, prolonged rainfall eventually by the end of the day with quite a bit of cloud cover. Time will tell. Often in such cases , if this does occur, we might see more storm coverage than anticipated. 

Otherwise, it appears some storm might even come to be on the 'stronger side' from near Canaveral and North from near Orlando and east toward Off shore up toward Daytona Beach and then more toward I-95 for  North Brevard late in the day. Some activity might be able to drift offshore even from Brevard and north (eventually), bit in the form of merely light rain or thunder is too soon to say.

TUESDAY-WEDNESDAY: So far these days appear will carry on the same themes more or less. Light west to east steering, ample moisture, and sea breeze collisions point to a rather 'on the wetter side' for July pattern, but not unusual.  Biggest hazard will be lightning and expect there will be quite a bit of it. Some storms might be able to press offshore the east coast or form near it even on some days with the strongest activity mostly limited to 5 miles of more from the coast except north of I-4; however, more details are needed for refinement as these days come . 

Expect we might be hearing that on either one or both of these days that 'some storms might be strong' (due to stronger surface wind gusts near the heavier storms  later in the day). All storms will bear the hazard of lightning, however, and seeing as how some of this activity could be close to the coast the threat of cloud to ground strikes near the beaches prior to the beginning of rainfall would present a precarious situation if that is the case.

THURSDAY-NEXT WEEKEND: Storm coverage might begin to decrease overall with most activity limited to 'away from the immediate coast' ..but again too far out in time to say.  The GFS shows most activity restricted to interior Central Florida during the late day sea breeze collisions with South Florida drying out a bit.

Over all, the next week looks like it could carry on perhaps three different summer themes in groups of 2-3 days at a time as the varying ridge axis' at different levels of the atmosphere toggle for position. Outside of that, what occurs each day might be slightly dictated by remaining boundaries that lie dormant from the previous day's activity.

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Friday, July 14, 2017

Pattern Change Begins Sunday Night - But Until Then...

Sunrise Friday Morning
TODAY: Another variation of the same theme since the post-tropical wave passage of Wednesday. Easterly flow will pile up moisture along the west coast, especially near to even west of I75 in the mid-late afternoon where the strongest thunderstorms will occur. Elsewhere sufficient moisture was in place for some showers earlier today, even some thunder from South Brevard on southward, but overall the air mass especially North Brevard northward is too dry in the mid-levels to produce much than a small rain shower in the absence of any synoptic scale disturbances.

SATURDAY-SUNDAY: Not much overall change to this pattern. The GFS shows East Central Florida to be 'especially dry' all things considered, whereas South Florida might see a surge of moisture on Sunday for greater coverage there. Otherwise, the Panhandle and spots along the west coast later in the day are the better areas for thunder with the spine of the state westward all potential clients of at least a rain shower.

SUNDAY NIGHT- MONDAY: Trough of low pressure over the northeast states (aloft) will carve south enough to shift the low level ridge axis to South Central Florida ending the easterly flow of recent days ..which will result  in morning offshore winds mainly north of West Palm (though quite light)..while the mid-level ridge aloft will meander somewhere across South Central to Central Direct. Thus, expect to wake up early to a completely different scenario at sunrise than will be the case the next two more mornings.

This overall scheme of things especially sets in around Tuesday, though there are some variations of the theme  in location as to where the ridge axis will be on any given day in particular;  it's just too soon to get into the nitty-gritty details. However, the scene is set it now appears for a new pattern to be established for several consecutive days in the next coming wee.

Overall, the period of MONDAY-FRIDAY appears will be one that sea breezes from both coasts will be at hand with enough moisture to play with, especially as they begin to converge on the center of the state with some days perhaps acquiring a slight leaning tendency to favor toward the east  just a bit for rainstorm and thunderstorm coverage. No days so far show enough of an easterly push for storms to work the whole way off the coast though, so many coastal locations (meaning within 1/2 mile of the beach) could well remain dry almost this entire upcoming week. Suspect many afternoons will end with much cloud cover however from anvil debris (at least)...and some outflows from inland might work their ways to the beaches...producing at least some showers.

Must point out that as this time approaches the forecast each day will greatly be contingent upon smaller scale parameters and localized 'events' such as outflow boundaries, lake/sea breezes, as well as exactly WHEN the early day activity actually gets going. All it takes is for a cluster of earlier day activity, even before sunrise (e.g. toward the Cedar Key area on the west coast) throw a wrench in the forecast for the entire day for some areas, especially in regard to the timing of when the best chances of rain will be. In other words, this time frame could be categorized as one of the 'typical summer' patterns, of which there are several.

TROPICS: The GFS is picking up on a tropical disturbance to enter the picture (potentially) by early next week to be located over the Western Caribbean region in general and to continue moving west and north in the general direction of South Florida in days to come; however, variations to this theme are already cropping up to include a tropical storm or even low end hurricane to curve well before reaching the state. 

The thing to consider is that it by that time it is not out of the question for tropical storms to begin to play a larger role in the long term forecast as we find our way out of the ' early-mid July lull".

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Saturday, July 8, 2017

Strong to 'Isolated Pulse Severe' Storms Possible Today Parts of the Interior

July 8, 2014  Storm Moves in on The Beaches
TODAY: Ample moisture , good surface heating and mixing ratios, with precipitable water values (PW) on the KSC sounding at 1.74" and 500mb temperature a cool -8 t0 -8.5C; Tampa is at 1.81 PW with similar 500mb temperature and both reading around 8C at 700mb ,  (as too is the same case with Miami) reveals fairly uniform conditions more or less across the region (peninsular North Central to South Florida). 

The surface ridge axis is approximately across a line running east -west across Lake Okeechobee whereas the mid level ridge axis is close to Central Florida to South Central Florida. Winds at all levels are generally 10kts or less...but from the west to southwest surface up through the mid-levels mainly north of a line running from Vero Beach to Sarasota.

What this all amounts to is both sea breezes to become active and progress inland in due time (but at what rate is always a mystery) with the area around the Big Bend and SE Florida to potentially 'go off' earlier along their respective sea breeze fronts which appears to be at hand already as of 11:55AM...

As this activity sets off outflows and propagates even newer activity going toward mid afternoon the sea breezes themselves will begin to work inland..further inland from Southeast Florida north and westward...and further inland toward the east and south from NW Florida.

All this 'should' come together with accompanying moisture convergence and Deep Moisture Convergence in the presence of colder air aloft and moderate instability in the lower levels to result in perhaps some water overloading aloft leading to strong downburst winds near heavier storms. 

Given the temperature profiles aloft (which are rather cool toward the colder side as far as the summer norm is concerned) a brief spurt of hail might also occur in some isolated storms which if the cards were to fall just right in isolated areas could result in Pulse Severe.

Activity might be able to find its way all the way to the beach proper mainly from near Oak Hill (southern Volusia) and north and toward US1 or I-95 further south. Local area affects along the eastern and north eastern banks of Lake Okeechobee will not be referred to at this point as those are too localized to be worth surmising due to the large scale overall scenario at hand today, though the 'potential' is there for that  area to have some anomalies to contend with as well.  

Some light rain even might be able to be realized at the beaches proper as far south as Central Brevard eventually accompanied by some rumbles aloft? We'll just have to see.

SUNDAY: Similar scenario in the all - in - all other than that temperatures aloft might not be quite as cold; on the other hand, the immediate beaches might have a better chance at rainfall on Sunday north of Vero Beach as the surface ridge takes its most sturdy plunge southward both at the surface and up through the mid levels resulting in better (though quite weak) west to east steering.

MONDAY: Pattern begins to change. Appears air aloft might warm as winds at most levels come to be more from the south to south -southeast direction. with moisture still around there might' be showers near the beaches early on but that activity would shift to the interior in rapid fashion working into mid afternoon.

TUESDAY-THURSDAY: Moisture from the old tropical system well out in the Atlantic is forecast to approach Florida . If so, it would be rather transparent to residents; just another day at the office more or less with maybe some showers nearer the coast earlier in the day ,  with maybe Thursday being 'that day of higher chances toward the west coast late in the day, and east coast early on'    ..then Friday might be a transition day...

BEYOND (yet still?): Upper level trough might dig south along the the Appalachians providing for better storm coverage toward the east side of the state again next weekend. Yet as we approach ...

(Magic Eight-ball Time: MONDAY and BEYOND of THE NEXT WEEK: All eyes might be on the tropics with a system that has been being forecast to move across or near Cuba and perhaps poise Florida as a target within 'eye' site. Too much uncertainty at this point. Historically speaking, there has been very little tropical activity to ever hit Florida prior to the last week of July that was above tropical storm status across all recorded (officially) history.

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