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Possible Noreaster Event Oct 18/19


SmokeEater

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Mt Holly's thoughts.

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...

THE GFS INITIALIZATION OF THE SYSTEM OVER THE GULF AND THE SHORT

WAVE EXITING THE ROCKIES WAS BETTER THAN THE WRF-NMM AND THE MODEL

WILL BE GIVEN MORE WEIGHT TODAY IN THE START OF THE LONG TERM. THE

SHORT WAVE IN THE ROCKIES IS CRITICAL AS ITS SPEED AND CAPTURING OF

THE GUFMEX LOW WILL BE THE DECIDING FACTOR AS TO WHETHER THE

TROPICAL PLUME CAN BACK IN TIME TO AFFECT OUR CWA (LIKE THE WRF-NMM

AND CAN GGEM HAVE) GO WIDE RIGHT AS THE GFS AND UKMET HAVE OR A

COMPROMISE BETWEEN THE TWO AS THE JUST IN ECMWF HAS.

THE OTHER MODEL TREND HAS BEEN FOR A SLIGHTLY SLOWER SOLUTION AND WE

SLOWED THE EVENT ABOUT 3 TO 6 HRS FROM OUR PREVIOUS PACKAGE. THE WAA

AND INCREASING ISENTROPIC LIFT SLUG OF THE PRECIPITATION IS EXPECTED

TO DEVELOP AND ADVECT RAPIDLY ACROSS OUR OUR CWA LATE TUESDAY NIGHT.

THE MODELS STILL HAVE SOME INSTABILITY ALOFT, MAINLY SOUTHEAST

TUESDAY OVERNIGHT AND WE CONTINUED OUR ISOLATED MENTION OF THUNDER.

AGREE THAT MINS MAY BE EARLIER IN THE NIGHT WITH A BUMP UP TOWARD DAWN

WHICH WE TRIED TO SHOW IN THE GRIDS.

THEN THE WAITING GAME COMES ON WEDNESDAY AS TO WHETHER OR NOT THE

TROPICAL PLUME CLIPS US. IN THE GFS SOLUTION, WE WOULD GET DRY

SLOTTED AND AFTER A FAIRLY PROGRESSIVE PULSE OF HEAVY RAIN IN THE

MORNING, THERE WOULD BE A LULL IN THE MIDDLE OF THE DAY OR EARLY

AFTERNOON. THE GFS IS NOT RAMPING WINDS AS MUCH IN THE EASTERLY FLOW

AROUND DAYBREAK ON WEDNESDAY. THIS TREND IF IT HOLDS REDUCES THE

CHANCES OF ADVY TYPE EASTERLY WINDS. THE WRF-NMM HAS NOT AND STILL

DOES NOT HAVE ADVY TYPE EASTERLY WINDS. WHAT THE WRF-NMM DOES HAVE,

BECAUSE OF ITS MORE WESTWARD SOLUTION ARE ADVY STRENGTH WARM

SECTOR SOUTH WINDS IN THE EASTERN PART OF OUR CWA. ITS TREND IS

ALSO WEAKENING THE LLJ BY ABOUT 15KTS VS YESTERDAY AND ALSO

DISPLACING MORE OFFSHORE (NOT AS OFFSHORE AS THE GFS).

THERE STILL WILL BE SUFFICIENT WIND ALOFT AS A CAUSE FOR CONCERN IF

A NARROW CONVECTIVE BAND CAN FORM NEAR THE COLD FRONT AND START

TAPPING THEM AS IT MOVES EASTWARD. WHILE THERE WILL BE INSTABILITY

ALOFT, FCST SFC BASED INSTABILITY RANGES FROM ALL ON THE WRF-NMM,

NONE WITH THE 00Z ECMWF AND DELMARVA FOR THE SREF AND GFS WHICH WE

WILL SIDE AS OUR AREA OF CONVECTIVE CONCERN. WE HEDGED HIER THAN

STAT GUIDANCE FOR MAX TEMPS SERN PART OF OUR CWA BECAUSE OF THE

POTENTIAL LULL IN THE PCPN.

CONVECTIVE RELATED PRECIPITATION SHOULD BE OVER (UNLESS THE MODELS

SLOW FURTHER) BY WEDNESDAY EVENING. A CHANNELIZED VORT MAX MIGHT

PROLONG CHANCES OF LIGHTER SHOWERS DEEPER INTO THE NIGHT. NO BIG

CHANGES TO THURSDAY AS SHORT WAVE ENERGY COUPLED WITH SELF DESTRUCT

SUNSHINE AND DEEPER MOISTURE SHOULD DEVELOP WIDELY SCATTERED TO

SCATTERED SHOWERS IN THE NORTHWESTERN PART OF OUR CWA. WHILE

THURSDAY WILL BE BRISK, SUSPECT THE CYCLONIC ISOBARIC CURVATURE

COUPLED WITH THE LACK OF A STRONG ISALLOBARIC PUSH WILL STOP US

SHORT OF WIND ADVISORY CRITERIA.

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There, someone is excited about the rain!

From what I've seen at 12z......GFS/NAM/Canadian all give a large dose of rain across our area. Hopefully the speed of things keeps rain amounts from getting way out of hand.

Yup, I don't see us getting OMFG amounts of rain. Too fast of a system. 1-3 maybe 4 tops, I would think. Highest being at the coast.

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Best jet dynamics are offshore , strongest short wave lags behind, fast Canadian flow meaning progressive system....double barrel low/dry slit

To contend with.

That dry slot could bring some clearing if

Timed right ahead of the frontal passage to create some better dynamics that what's being progged, and that's a big if. But it would be enough to fire up a sqaull line or enhance one enough to increase

Overall qpf

Totals. Mt holly alluded to that in the morning afd. Like smoke eater said, nothing crazy outta this storm.

On a side note, we'd be having weenie suicides if this was 2 months later if you actually watch the dynamics at play shifting. You'd be hearing waa, TORCH! lolz

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Yup, I don't see us getting OMFG amounts of rain. Too fast of a system. 1-3 maybe 4 tops, I would think. Highest being at the coast.

the wildcard of course being how the models handle the system coming out of the gulf...if it stays a distinct entity as it comes north and if the precip field expands....would not take much of a shift west to bring heavy rain farther west, taking us from a disruptive heavy rain to legit flash flood threat....though the past few runs seem pretty insistent on keeping the absolute heaviest either right on the coast or just offshore. friends have been asking me about 'this first big noreaster' and I keep playin it down, i just hope the wildcard stays in the deck.

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Best jet dynamics are offshore , strongest short wave lags behind, fast Canadian flow meaning progressive system....double barrel low/dry slit

To contend with.

That dry slot could bring some clearing if

Timed right ahead of the frontal passage to create some better dynamics that what's being progged, and that's a big if. But it would be enough to fire up a sqaull line or enhance one enough to increase

Overall qpf

Totals. Mt holly alluded to that in the morning afd. Like smoke eater said, nothing crazy outta this storm.

On a side note, we'd be having weenie suicides if this was 2 months later if you actually watch the dynamics at play shifting. You'd be hearing waa, TORCH! lolz

It's not a pretty system if this were December/January. Shore might get a couple of inches of rain...I'm not sure Philly does much more than an inch out of this...most of the best moisture plume from the tropical system will graze the region but not hit everyone.

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Saw the 00z models this morning, good thing its not winter in eastern PA or the snow-weenies would be raging!.

Honestly, at this point I have little faith in any models.....as others have said, Jersey looks more in line for a soaking than points further west. We'll see what 12z shows.

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when did I miss this bit of news? A new NAM is out eh? Do you know what they hoped to accomplish with this newer version? Less convective feedback? Better 48 hour skill, etc?

The implementation was delayed, was initially suppose to occur in July. I've just read its overall better. They are also going to be dropping some of the ancient rsm and eta members of the sref in the not too distant future also. A closer to 4dvar gfs is suppose to start in 2012.

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The implementation was delayed, was initially suppose to occur in July. I've just read its overall better. They are also going to be dropping some of the ancient rsm and eta members of the sref in the not too distant future also. A closer to 4dvar gfs is suppose to start in 2012.

According to dtk, it's a 3DVAR hybrid with an ensemble Kalman filter

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The implementation was delayed, was initially suppose to occur in July. I've just read its overall better. They are also going to be dropping some of the ancient rsm and eta members of the sref in the not too distant future also. A closer to 4dvar gfs is suppose to start in 2012.

A 4dvar GFS should improve the GFS even more. I've noticed the GFS catching up to the Euro in some areas such as tropical. Hopefully, it will do as well as the Euro in sniffing out winter weather. It must be tough for you guys to relearn tendencies with models when they have these changes.

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A 4dvar GFS should improve the GFS even more. I've noticed the GFS catching up to the Euro in some areas such as tropical. Hopefully, it will do as well as the Euro in sniffing out winter weather. It must be tough for you guys to relearn tendencies with models when they have these changes.

The GFS has definitely performed worse in the tropics in 2011 compared to 2010. It is clearly back to #3 amongst the global models again. EMC is aware of the problems, but unsure what the cause(s) is. Since the GFS EnKF has performed so well this year, there is hope that changing the initialization this spring will help fix the issues.

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The GFS has definitely performed worse in the tropics in 2011 compared to 2010. It is clearly back to #3 amongst the global models again. EMC is aware of the problems, but unsure what the cause(s) is. Since the GFS EnKF has performed so well this year, there is hope that changing the initialization this spring will help fix the issues.

Okay, since we're keeping score, what's currently #2 after the Euro?

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The GFS has definitely performed worse in the tropics in 2011 compared to 2010. It is clearly back to #3 amongst the global models again. EMC is aware of the problems, but unsure what the cause(s) is. Since the GFS EnKF has performed so well this year, there is hope that changing the initialization this spring will help fix the issues.

okay. I was going by the first 3-5 storms this year, where the GFS performed well. I didn't notice the trail off later, but I'll take your word that it did. I did note the GFS EnKF perform well with later storms, and since that has the kalman filter, that is good to know. thanks

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Hopefully the Kalman Filter can help improve the NAM as it seems to have worked well on the GFS EnKF. We all know the NAM needs some help lately.

Well, today's 12z was the first run with the new model physics and grid. I don't actually know what kind of initialization scheme the NAM uses, since it is gridded instead of spectral.

Here is a link to the changes: http://www.nws.noaa.gov/om/notification/tin11-16nam_changes_aac.htm

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