"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, March 20, 2018

"Risk" of All Modes of Severe Weather Being Possible Today

The "Good Friday" Severe Storm - 2016
TODAY: Very little change in thinking from previous post the other day. 

A prefrontal boundary across North Florida will start to become 'active' come late morning toward the Big Bend area south and eastward toward the Gainesville  - St Augustine line (mainly) and south.

As stronger wind aloft in the mid-levels begins to coincide with the leading edge of a jet stream speed max now entering the north Gulf and poised to approach the area mainly from I-4 and north heading to mid -afternoon activity should increase in coverage and intensity due to the resultant bulk-shear up through the atmosphere  coupled with daytime heating.

Mid level lapse rates in this area accompanied by bulk-shear (mainly speed shear with some directional shear as well) in between the 5000-20,000 foot levels and ample low level instability with very cold air aloft could produce storms with 'damaging hail' and/or straight line winds. A tornado cannot be completely ruled out.

The time frame for the areas of North Florida southward through Volusia County is from  around 1pm - 4pm.

Further south, daytime heating will have had more time to work over parts of North Central - Central Florida (assuming this timing is correct) and that there is good insolation ( not too many high clouds spreading over this area), which will result in  'better' low level lapse rates as well. 

This 'window of opportunity' of better low level lapse rates will coincide with the 'increasing winds aloft through the mid-levels' over-spreading the area south of I-4 as the jet speed max approaches the state (as noted above) enhancing upper level divergence producing greater lift in the atmosphere.

Thus, as of this time ( 5:00AM) the 'line of activity' and possible random storm cells out ahead of the main-thrust of activity could see an up-tick in the hours between 3-6PM as the pre-frontal trough pushes East to East South East across the state. 

The time frame currently anticipated for the Southern Volusia -Orange-Seminole - North to Central Osceola - and most of Brevard Counties of the 'highest risk' of 'potentially severe storms' is between 3pm - 7pm as activity presses east and south across the peninsula as day-time heating will be reaching it's peak and resultant surface based CAPE (convective available potential energy) increases.

Note that time frames noted above are subject to change, as are conditions, once later model runs are released and made available during the late morning hours (generally after 10:30AM - noon time).  'Potentially' a region in the Enhanced Risk area (see below) might be upgraded to Moderate Risk, and if so suspect it would be for the region generally 30 miles north and south of the Daytona Beach area. But , again, that is nothing but surmising.

BLOG "Forecast" From Previous Post

Above was the 'forecast' (blog only) for today from the other day, and below is the latest SPC outlook. 

SPC OUTLOOKS are available 'HERE"

It is 'highly recommended' that access to media outlets , whether by weather radio or even one's trusted television station be at hand to monitor potential threats in one's specific location going into early-mid afternoon.

Again, above is the 'best guess' risk area from a few days ago in the previous post, and the latest advisory issued by the Storm Prediction Center (SPC) located in Norman, Oklahoma . As can be seen, the forecasters at The SPC have determined there is an Enhanced Risk (which is greater than a Slight Risk) for parts of mainly North - North Central Florida. A later update will be released around 8AM EDT with another to follow around 12:30PM EDT.

Side note: "Celestial" Spring begins at 12:15PM EDT, today as the sun will be passing over the the equator heading toward the Tropic of Cancer at which point is the first day of 'Summer' (in late June).

Activity should quickly weaken, assuming the current timing of activity being depicted by the 4KM NAME and High Resolution  Rapid Refresh (HRRR) models coincident with sunset, as the central low level axis (pre-frontal trough) progresses further south toward Ft Pierce - West Palm Beach areas and stronger wind in the mid-levels shifts off the east coast of Central -South Central Florida.

WEDNESDAY: Breezy NW wind all day and dry. Colder air is on the way for Thursday- Saturday morning, but Wednesday will still see the 70Fs despite the wind.

THURSDAY-FRIDAY: Cooler again with lows ranging in the mid-40Fs to lower 50Fs and highs in the mid-upper 60FS most areas but touching the lower 70Fs Friday. Thursday will be quite breezy going into Friday , but the wind will quickly diminish going through Friday and into the weekend.

FRIDAY-AFTERNOON and BEYOND: Warming to normal to even above normal temperatures this weekend , and dry with light wind. Cooler sea-side with the sea breezes in place, with highs at the beaches more than likely in the 70Fs.

The next chance of rain is currently being shown (easily subject to change) in the period from near Good Friday - Easter Sunday or a day or two either side of that period. No cold air influx , at least as cool as it will be Thursday - Saturday morning, is being shown to arrive at all at this point, but rather a frontal boundary is to press into the Southeast States and eventually Central Florida and wash out. This could change, however.

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Saturday, March 17, 2018

First Day of Spring (Tuesday) Might Come in Like a Roaring Severe Lion

Dandelion , March 17, 2016  
TODAY- SUNDAY: Warming trend has commenced and will continue through Tuesday. Though Sunday and Monday mornings will still be on the cool side, a quick warm up toward mid-morning will ensue, with temperatures running at to just a bit above normal. Atmosphere will gradual moisten a bit so it won't be quite as dry. Meanwhile, a complex mid-upper level low pressure system is already beginning to take shape from the Southern Plains states toward the Southeast states, which will move toward the east coast through Tuesday.
This system will be responsible for severe weather threats across multiple states in the next few days.

MONDAY: The 'risk' of the first of two impulses could impact the state mainly North - North Central areas. Latest GFS is showing sufficient low level instability, cold air aloft, and wind shear aloft to support strong storms mainly north of a line from Clearwater area (west coast) toward Sebastian or Vero Beach (east coast). Better risk will be north of I-4. This day is still questionable as earlier guidance was barely squeezing out a rain shower toward the east coast late in the day. The latest run is much more aggressive so bears watching.

TUESDAYTuesday is the First Day of Spring, beginning at 12:15PM EDT, most fitting for the cliche of March (or Spring) coming in like a Lion and goes out like a Lamb. Any truth to it? Not Really. 

 Risk of severe storms roaring through appears to be increasing.

 GFS has been consistent in the potential now for two days, and the latest run only increased that potential several notches. Ample surface based instability, cold air aloft, and strong speed shear aloft is forecast as the nose of a 120 knot jet stream wind aloft points to passing right over North Central Florida    enhancing lift right during the time of peak heating.  Bulk shear of 50-70kts between 10-20,000 feet aloft added in definitely points to 'Severe Parameters'.  Directional shear is lacking a bit at this point however.

All said parameters align ahead of a prefrontal trough and cold front, with the boundary as it stands now to enter Central Florida during to just after peak heating hours through sunset. Timing of course could easily change on the system during the next 48 anticipated hours, but chances are we will begin to hear about it on the evening local news stations. 

  As of Today the biggest threat appears to be South of I-10 and north of Route 60 or roughly north of a Vero Beach to Sarasota Line on Tuesday. Strong storms possible from a line running toward Melbourne to South Tampa Bay on Monday but this is quite sketchy still.

Given this is still several days out the apparent 'most at risk' area  is subject to change/ intensity modifications. The Storm Prediction Center is already watching all of Central Florida on Tuesday for a 'severe risk' with parts of North Florida on Monday.

WEDNESDAY - BEYOND: Cooler and breezy Wednesday into Thursday. Coldest air does not reach the peninsula until over night Wednesday through all of Thursday into Friday. Looks like temperatures will cool to below normal once again, but not as cold as this last go around. At this stage it looks like we'll recover to near normal temperature range a bit quicker as well, so that by the weekend all will be 'near normal'. No other rain chances in sight at least until Easter time frame (at least).

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Saturday, March 10, 2018

A Little Gnarly Come Sunday into Monday - Then Colder Again

TODAY: Per satellite image below and a rather complicated evolution of mid level lower pressure over the Southeast states in the next 48 hours, the forecast for timing of any rain / storm events and the nature of them is still rather sketchy. In the previous post (Tuesday) it was mentioned there could be possibly strong storms on Sunday. That has not changed.

Otherwise for today, slowly warming and moistening of the atmosphere (finally)  with increasing high level clouds especially South and South Central later in the day (it now appears). Otherwise light Southeast wind and rain free other than maybe later more toward South Florida.


SUNDAY: Sunrise will be at 7:36AM and sunset at 7:28PM.

Pre-frontal type trough ahead of a developing cold front to enter the picture across Florida in the midst of warmer temperatures again but with cold air aloft, increasing moisture, and destabilizing atmosphere with increasing wind shear and some directional shear points to possibly even 'rotating storms' (at least slightly) if they can get going. Best chance of rain from early to mid-morning west coast working east though some activity might be able to go up toward the east coast (mainly south of I4) on it's own some time after 1PM.

Still looks like with directional/speed shear and sufficient surface based instability and cold air aloft the potential remains for strong storms. Some areas could see some 'good rain' in the next 48 hours but then again some locations might end up with very little to none at all.  The rain chances shift south going into Monday afternoon (eventually).

Noting , that the OFFICIAL FORECAST from the Storm Prediction Center (SPC)  is also eyeing North Florida on Sunday for Strong storms

MONDAY : Frontal boundary should be near Central Florida before sunset as rain chances end. Again a chance of showers or thunder on Monday mainly south of I-4 with temperatures still in the mid-upper 70Fs and some lower 80Fs possible. Sun will be setting Monday evening at 7:29 PM.

TUESDAY - WEDNESDAY: Front will have cleared. Breezy and cool like it was this last go around. Dry as well, which does not fair well at this time of year with increased fire risk.

THURSDAY: Another front might well go through in a secondary surge of what is now showing to be extremely  and unusually dry air for this time of year. Colder yet again with this surge but we round the corner pretty quickly going into the week end after which no rain or cold air is foreseen for quite some time afterward.

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Tuesday, March 6, 2018

Chances of Rain Tonight/Early Wednesday (& Storms Sunday )

Surfing at Jetty Park Cape Canaveral, Florida
TODAY - TONIGHT: Warmer and breezy with south - southwesterly wind . Mainly 'sunny' south of I-4 the majority of the day. Cold front now cutting through the panhandle (see below) to work toward the I-4 come late overnight   to be near a Cape Canaveral - Sarasota line between 7-8AM Wednesday morning. Chance of showers and maybe even some thunder with the front mainly near the West Coast from Sarasota northward and along to north of I-4.

WEDNESDAY: After front works through early in the day (Central) and later in the day (South) westerly type wind in the 10-15 mph. Though with the front there might be a brief period of gustier wind it  appears that will wane off as the day progresses. Clearing sky with highs in the lower-mid 70Fs.

THURSDAY-SATURDAY MORNING: Much cooler, akin to the past 'cool spell' with interior morning lows in the lower 40Fs up toward the mid-upper 40FS more widely spread. Appears the immediate Barrier Islands of Brevard and south  will see closer to lower 50FS and warmer still far South Florida. Wind will not be quite as breezy though as it was the past few days during our previous cooler period as highs strain to reach even 70F on Thursday and Friday or if they do, it would be but for only a brief time.

SATURDAY AFTERNOON- SUNDAY: Next front on the way. This boundary and accompanying 'air mass' might yield a better overall rain chance , and there might also be some storms (possibly strong) along with it. 

Atmospheric Parameters that would support stronger storms have been continuously showing up now for several days in the GFS guidance, but exactly when and where (if so) is hard to say other than 'somewhere closer to and south of I-4" between early Sunday morning to as late as Sunday night' (depending on ones location). In short, nothing definite yet but still looks like some much needed rain will again be on the way, with the 'threat' of possibly stronger activity with it.

Cool again after this frontal passage  but nothing more than what we just saw and will see come this Thursday- Saturday morning .

Latest GFS has a secondary boundary coming through "Monday" that could potentially yield showers or storms again,  but that is a new 'card in the deck' and not sold on it just yet. If it is out of it's league, then after Sunday there would not be a rain chance again Monday nor will be one for at least a week to follow.

FAR OUT: Long range guidance implies several more opportunities for rain or storms spread out about 6-10 days apart from each going into early April, which is about the norm this time of year. Any rain would be a good thing, given we are in the midst of and slowly nearing the end of the 'Dry Season" (the "Wet Season 'typically beginning  to as early as the last 10 days of May or  as late as the second week of June, depending on the year).

SATURDAY NIGHT: Day Light Savings Time begins -

 Set clocks Forward one hour before hitting the sack Saturday night.

Sun will rise later in the morning, but set later in the early evening.

Days continue to get longer on either end by a minute or so
 all the way to June 21.

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