Little change to 96L; El Salvador flood among its worst in history

By: Dr. Jeff Masters , 2:55 PM GMT on October 22, 2011

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A region of disturbed weather in the Western Caribbean (Invest 96L) is bringing heavy rains to coastal Nicaragua and Honduras, and has the potential to develop into a tropical depression Sunday or Monday. Visible satellite loops show that 96L has changed little in organization since yesterday. Some rotation is apparent, but the heavy thunderstorm activity is quite limited due to a large region of dry air to the east, as seen on water vapor satellite loops. There are no signs of a surface circulation. Surface pressures have been falling since Thursday at San Andres Island, near the center of 96L. Wind shear is a moderate 10 - 20 knots in the region, and is expected remain in the moderate range through Tuesday. Water temperatures are very warm, 29 - 30°C, and these warm waters extend to great depth.


Figure 1. Morning satellite image of 96L.

Forecast for 96L
The moderate wind shear and warm waters should allow for some development of 96L over the next few days, though this will be slowed by the dry air to the storm's east, and perhaps by proximity to the land areas of Nicaragua and Honduras. The models are less enthusiastic today about developing 96L into a tropical depression than they were yesterday. The ECMWF no longer predicts development, and the GFS and NOGAPS predict only weak development before 96L moves ashore over Honduras on Tuesday. On Wednesday, a strong trough of low pressure will be passing over the Eastern U.S., and this trough has the potential to turn 96L northwards into Western Cuba. This is more likely to happen if 96L is stronger and deeper, and thus able to "feel" the upper-level winds the trough will bring. The UKMET model predicts 96L will develop into a tropical storm that moves through the Yucatan Channel between Cuba and Mexico on Thursday. If 96L remains a weak and shallow system, though, it is more likely to stay trapped in the Western Caribbean and make landfall in Nicaragua or Honduras. NHC gave 96L a 60% chance of developing into a tropical depression by Monday in their 8 am Tropical Weather Outlook today. The hurricane hunter mission scheduled for today was cancelled due to the lack of development of 96L; the mission has been re-scheduled for Sunday afternoon.

97L
A broad region of low pressure near 10°N, 57°W, about 400 hundred miles east of Trinidad (Invest 97L), is moving slowly west-northwest towards the Lesser Antilles Islands. This low has very limited heavy thunderstorm activity, due to dry air to the northwest. NHC is giving 97L just a 10% chance of developing into a tropical depression by Monday. 97L is under a moderate 10 - 20 knots of wind shear, and this shear is expected to drop to the low range, less than 10 knots, by Monday, when the storm will be in the Eastern Caribbean Sea. By the time 97L approaches Jamaica in the Central Caribbean in 5 - 6 days, the storm should find a moister environment, and there is a chance for 97L to develop into a tropical depression, as predicted by the NOGAPS model.


Figure 2. Rainfall in El Salvador for the 10-day period ending on Friday, October 21, at 8 am EDT. At Huizucar, an astonishing 1.513 meters (4.96 feet) of rain fell during those ten days. Image credit: Hydrological Service of El Salvador.

Death toll from Central American rains rises to 105
“I want to tell the world that El Salvador is going through one of the most dramatic disasters in its history,” President Mauricio Funes said on national radio and television Wednesday night, as he appealed for international aid. A week of torrential rains across Central America have triggered extreme floods and landslides that have killed 105 people, according to media reports. El Salvador, Guatemala, Honduras and Nicaragua have declared states of emergency due to the disaster. El Salvador and Guatemala have seen the worst flooding, with 34 and 38 people killed, respectively. Another 18 have died in Honduras, 13 in Nicaragua, and 5 in Costa Rica. The rains were due to a large area of low pressure that was moistened by the landfall of Tropical Depression 12-E near the Mexico/Guatemala border last week. Contributing to the record-intensity rains were ocean temperatures off the coast of El Salvador that were 0.5 - 1°C above average during the first half of October, allowing more water vapor than usual to evaporate into the air. Over the past ten days, rainfall amounts of over a meter (39.4") have fallen over a large area of southwest El Salvador (Figure 2.) At Huizucar, an astonishing 1.513 meters (4.96 feet) of rain fell in the past ten days.

I'll have a new post on Sunday.

Jeff Masters

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and if avila is in charge tomorrow he would probably cancel recon also
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Quoting stormpetrol:
Link

96L much more organized IMO.
Decent swirl and rotation there, I guess a good kick in the DMAX and she will be tooting her horn.
Member Since: August 31, 2009 Posts: 0 Comments: 5628
9.5n55.4w, 9.6n55.6w, 9.8n55.8w have been re-evaluated&altered for Invest97L's_6pmGMT_ATCF
9.7n55.3w, 9.8n55.4w, 9.9n55.5w, 10.2n55.6w are now the most recent positions
Starting 21Oct_6pmGMT and ending 22Oct_6pmGMT

The 4 southern line-segments represent Invest97L's now northnorthwestward path

Copy&paste pmv, bgi, 9.6n55.1w-9.7n55.3w, 9.7n55.3w-9.8n55.4w, 9.8n55.4w-9.9n55.5w, 9.9n55.5w-10.2n55.6w, dcf into the GreatCircleMapper for more info

The previous mapping (for 22Oct_12pmGMT)
Member Since: August 21, 2007 Posts: 0 Comments: 4860
IMO.. 40% or even 30% at 8pm, especially if Avila is on duty.

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24 mph WNW wind, pressures significantly lower , though its that time of the evening, area moistening to the east? 96L got alot going for it I would say
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i would probably say the next TWO will remain the same 50% with different wording
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Quoting stormpetrol:
96L is moving slowly just a tad east of due North, IMO this could be called a 30mph TD at this point, JMO.
agree but more convection needs to fire over the center
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Will sure be interesting to see the TWO at 7 CST.
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96L is moving slowly just a tad east of due North, IMO this could be called a 30mph TD at this point, JMO.
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Well i was hoping this last decent MJO pulse was going to pull off some surprises.
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Quoting TropicalAnalystwx13:

You said to wake you up when the season was active again...Its not, so you may want to go back to sleep. ;)

k...zzzz :)
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Quoting TropicalAnalystwx13:

No need to apologize in that case. :P
tropical looking at visible images looks to me 96L is starting to get going the dry air to its NE is starting to abate
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intresting to note how convection has continued to fire near the western edge of the center and apparant banding features developing on the east side , looks to me its is slowly organizing but will take time
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Quoting WoodyFL:


I hope you have me confused with someone else. I have only been on here since the Spring and only made about 170 posts. I don't recall posting anything to you in the past two days, although I might have. I dont' recall ever saying anything negative to anyone. If I said anything you took as negative, I apologize.

No need to apologize in that case. :P
Member Since: July 6, 2010 Posts: 113 Comments: 32335
Quoting TropicalAnalystwx13:


What's your problem? You've had a real sucky attitude towards me the past two days.


I hope you have me confused with someone else. I have only been on here since the Spring and only made about 170 posts. I don't recall posting anything to you in the past two days, although I might have. I dont' recall ever saying anything negative to anyone. If I said anything you took as negative, I apologize.
Member Since: April 24, 2011 Posts: 1 Comments: 601
Quoting robert88:


Yep...crazy the global models have completely dropped it...however vertical instability is at it's lowest since early June. Looks like the air column is just too stable to get anything going. This season needs to be studied BIGTIME.

You said to wake you up when the season was active again...Its not, so you may want to go back to sleep. ;)
Member Since: July 6, 2010 Posts: 113 Comments: 32335
Quoting Sfloridacat5:
18Z, GFS fails to develop 96L. It's hard to believe this same model was so aggressive with the system yesterday.



Yep...crazy the global models have completely dropped it...however vertical instability is at it's lowest since early June. Looks like the air column is just too stable to get anything going. This season needs to be studied BIGTIME.
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Current Weather Conditions:
San Andres Isla / Sesquicentenario, Colombia
(SKSP) 12-35N 081-43W 6M
Conditions at

2011.10.22 2200 UTC
Wind from the WNW (300 degrees) at 18 MPH (16 KT)
Visibility greater than 7 mile(s)
Sky conditions mostly cloudy
Temperature 78 F (26 C)
Dew Point 73 F (23 C)
Relative Humidity 83%
Pressure (altimeter) 29.73 in. Hg (1006 hPa)
ob SKSP 222200Z 30016KT 9999 FEW016 BKN200 26/23 A2973
Member Since: October 9, 2008 Posts: 0 Comments: 8399
18Z, GFS fails to develop 96L. It's hard to believe this same model was so aggressive with the system yesterday.

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Quoting stormpetrol:
Link

96L much more organized IMO.


If not, it is trying hard. Tonight should be interesting to watch.
Member Since: April 24, 2011 Posts: 1 Comments: 601
Quoting FLWeatherFreak91:
Most of the circulation is offshore according to ascat.


Yes, I know. Just making a point that when systems are too close to land masses they often have trouble developing and get a good inflow. In this case from the Southwest.

Member Since: April 24, 2011 Posts: 1 Comments: 601
Link

96L much more organized IMO.
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12.8n81.7w has been re-evaluated&altered for Invest96L's_22Oct_6pmGMT_ATCF
12.9n81.4w, 13.2n81.4w are now the most recent positions
Starting 21Oct_6pmGMT and ending 22Oct_6pmGMT

The 4 line-segments represent Invest96L's now northward path
Copy&paste ahs, puz, adz, 13.5n80.2w-13.0n80.5w, 13.0n80.5w-12.7n80.7w, 12.7n80.7w-12.7n81.2w, 12.7n81.2w-12.9n81.4w, 12.9n81.4w-13.2n81.4w, pva into the GreatCircleMapper for more info

The previous mapping for 22Oct_12pmGMT
Member Since: August 21, 2007 Posts: 0 Comments: 4860
.
Member Since: April 24, 2011 Posts: 1 Comments: 601
Quoting TropicalAnalystwx13:



Yeah, thats a tad high.
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Quoting WoodyFL:


Ive noticed that. I guess it depends on how strong it might get. It should make a difference. With it being so close to land, it doesn't help with the intensification.
Most of the circulation is offshore according to ascat.
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Quoting wn1995:


Also, initiation is about to occur inside the watch area. Will be interesting to watch it unfold this afternoon. Very large hail will be possible in initially discrete supercells. Then a nice MCS may get going with some wind damage possible. I won't even completely rule out a tornado or two... LCL values are just a tad high.

Member Since: July 6, 2010 Posts: 113 Comments: 32335
Quoting stormwatcherCI:
The last two surface maps show 96L moving N. Previous one had 97L going NW but have shifted back W.





Ive noticed that. I guess it depends on how strong it might get. It should make a difference. With it being so close to land, it doesn't help with the intensification.
Member Since: April 24, 2011 Posts: 1 Comments: 601
Quoting TropicalAnalystwx13:

I know, lol...I just checked that site and saw it.


Also, initiation is about to occur inside the watch area. Will be interesting to watch it unfold this afternoon. Very large hail will be possible in initially discrete supercells. Then a nice MCS may get going with some wind damage possible. I won't even completely rule out a tornado or two... LCL values are just a tad high.
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Center under the convection? I think so.

Member Since: July 6, 2010 Posts: 113 Comments: 32335
Quoting wn1995:


Been out for a while, lol ;)

I know, lol...I just checked that site and saw it.
Member Since: July 6, 2010 Posts: 113 Comments: 32335
Quoting TropicalAnalystwx13:
First Severe Thunderstorm Warning of the day:

575
WUUS54 KOUN 222131
SVROUN
OKC053-071-222230-
/O.NEW.KOUN.SV.W.0580.111022T2131Z-111022T2230Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE NORMAN OK
431 PM CDT SAT OCT 22 2011

THE NATIONAL WEATHER SERVICE IN NORMAN HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
SOUTHEASTERN GRANT COUNTY IN NORTHERN OKLAHOMA...
KAY COUNTY IN NORTHERN OKLAHOMA...

* UNTIL 530 PM CDT

* AT 431 PM CDT...NATIONAL WEATHER SERVICE RADAR INDICATED SEVERE
THUNDERSTORMS ALONG A LINE EXTENDING FROM 4 MILES SOUTHEAST OF
MEDFORD TO 6 MILES SOUTH OF NARDIN...MOVING EAST AT 15 MPH.

HAZARDS IN THE WARNING INCLUDE...
HAIL UP TO THE SIZE OF HALF DOLLARS...
WIND GUSTS TO 60 MPH...

* LOCATIONS IN THE WARNING INCLUDE BLACKWELL...DEER CREEK...
KILDARE...LAMONT...MEDFORD...NARDIN...NEWKIRK...PE CKHAM...PONCA
CITY...TONKAWA AND WESTERN KAW LAKE.

THIS INCLUDES INTERSTATE 35 BETWEEN MILE MARKERS 208 AND 228.

LAT...LON 3695 9688 3675 9687 3673 9690 3668 9693
3669 9702 3668 9706 3664 9704 3659 9705
3660 9769 3684 9781
TIME...MOT...LOC 2131Z 272DEG 14KT 3675 9769 3672 9743



BURKE

CLICK HERE TO GO TO PREVIOUS BULLETINS.


Been out for a while, lol ;)
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First Severe Thunderstorm Warning of the day, albeit, a little old.

575
WUUS54 KOUN 222131
SVROUN
OKC053-071-222230-
/O.NEW.KOUN.SV.W.0580.111022T2131Z-111022T2230Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE NORMAN OK
431 PM CDT SAT OCT 22 2011

THE NATIONAL WEATHER SERVICE IN NORMAN HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
SOUTHEASTERN GRANT COUNTY IN NORTHERN OKLAHOMA...
KAY COUNTY IN NORTHERN OKLAHOMA...

* UNTIL 530 PM CDT

* AT 431 PM CDT...NATIONAL WEATHER SERVICE RADAR INDICATED SEVERE
THUNDERSTORMS ALONG A LINE EXTENDING FROM 4 MILES SOUTHEAST OF
MEDFORD TO 6 MILES SOUTH OF NARDIN...MOVING EAST AT 15 MPH.

HAZARDS IN THE WARNING INCLUDE...
HAIL UP TO THE SIZE OF HALF DOLLARS...
WIND GUSTS TO 60 MPH...

* LOCATIONS IN THE WARNING INCLUDE BLACKWELL...DEER CREEK...
KILDARE...LAMONT...MEDFORD...NARDIN...NEWKIRK...PE CKHAM...PONCA
CITY...TONKAWA AND WESTERN KAW LAKE.

THIS INCLUDES INTERSTATE 35 BETWEEN MILE MARKERS 208 AND 228.

LAT...LON 3695 9688 3675 9687 3673 9690 3668 9693
3669 9702 3668 9706 3664 9704 3659 9705
3660 9769 3684 9781
TIME...MOT...LOC 2131Z 272DEG 14KT 3675 9769 3672 9743



BURKE

CLICK HERE TO GO TO PREVIOUS BULLETINS.
Member Since: July 6, 2010 Posts: 113 Comments: 32335
Quoting TropicalAnalystwx13:

Yes, a turn westward is supported, but not tomorrow. Heights, pressures, or whatever you want to call them, are too high for a system just to turn westward and move into Central America like that. It is still likely that it will meander in the general vicinity over the coming days, or potentially drift northward before high pressure briefly builds in and makes the storm move more westward before it feels the effects of that strong trough you mentioned.


Heights to the West really aren't that high. And generally should lower over the next 24 hours. Heights to the North are higher, anyway. Anything it does will be slow, that we can agree on.
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The pressure at San Andres Island is 1007.11 mbar.
Member Since: July 6, 2010 Posts: 113 Comments: 32335
Quoting wn1995:


It certainly does not need to be ignored. a Turn more westwards is supported. It is still possible for it to be picked up by the trough that is going to dip down mid next week, which was my original prediction, but it doesn't look as likely as it did yesterday.

Yes, a turn westward is supported, but not tomorrow. Heights over Honduras/Nicaragua are too high for a system just to turn westward and move into Central America like that, kind of like when a tropical cyclone moves towards the center of a high pressure (It isn't possible). It is still likely that it will meander in the general vicinity over the coming days, or potentially drift northward before high pressure briefly builds in and makes the storm move more westward. Then, it should begin to "feel" the trough you mentioned.
Member Since: July 6, 2010 Posts: 113 Comments: 32335
Quoting TropicalAnalystwx13:

I don't understand where Avila gets that from...Steering currents are very weak, and high pressure centered over Central America would definitely not allow for 96L to move in that direction.

So, yeah, despite them being the experts, I'd ignore that. We'll probably see different wording at 8PM.


It certainly does not need to be ignored. a Turn more westwards is supported. It is still possible for it to be picked up by the trough that is going to dip down mid next week, which was my original prediction, but it doesn't look as likely as it did yesterday.
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Quoting Neapolitan:

That mid/late-week front looks like a solid one with which to close out October. The Tuesday high in Oklahoma City is 84, while on Wednesday it's 59; in Topeka, it's 76 then 53; in Amarillo it's 81 then 52. And it's pretty much the same story throughout the region--and, as your comment indicates, there's only a slightly elevated chance of showers during the frontal passage; it's gonna be a dry one.

Sorry about that...
Quoting Neapolitan:

That mid/late-week front looks like a solid one with which to close out October. The Tuesday high in Oklahoma City is 84, while on Wednesday it's 59; in Topeka, it's 76 then 53; in Amarillo it's 81 then 52. And it's pretty much the same story throughout the region--and, as your comment indicates, there's only a slightly elevated chance of showers during the frontal passage; it's gonna be a dry one.

Sorry about that...
It looks like it will remain dry in South Central Texas for some time? Should end October without any more rain. At least I got 2 inches 2 weeks ago but that is long gone.
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Quoting stormpetrol:


Actually to me 96L has moved very little if at all in the last 4-5 hours, I still have it 13N/81W










Look at the image Patrap posted in #285. It is closer to 14N than it is to 13N.
Member Since: October 9, 2008 Posts: 0 Comments: 8399
Quoting stormwatcherCI:
I know but some people are saying it looks like it is moving west.


Actually to me 96L has moved very little if at all in the last 4-5 hours, I still have it 13N/81W










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too me nothing has chang with 96L from the 2pm update so am thinking at lest 30-50% some where in there
Member Since: May 21, 2006 Posts: 5091 Comments: 115252
Quoting stormpetrol:
What will the % of 96L be at 8pm EST , I say 60-70%!
Your guess is as good as mine. If we say 60% they say 70%. If we say 70% they will say 60%.
Member Since: October 9, 2008 Posts: 0 Comments: 8399
The water is warm,
but it's sending me shivers.
A baby is born,
crying out for attention.

Memories fade,

like looking through a fogged mirror
Decision to decisions are made and not bought
But I thought,
this wouldn't hurt a lot.
I guess not



AL962011 - INVEST

Storm Relative 1km Geostationary Visible Imagery




Member Since: July 3, 2005 Posts: 426 Comments: 128865
Quoting jrweatherman:
FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

THE AREA OF LOW PRESSURE IN THE SOUTHWESTERN CARIBBEAN SEA IS NOW LOCATED A LITTLE BIT LESS THAN 100 MILES NORTHEAST OF SAN ANDRES ISLAND. THE LOW IS CURRENTLY DRIFTING NORTHWARD...BUT STRONG HIGH PRESSURE TO THE NORTH SHOULD FORCE THE LOW TO MOVE TOWARD CENTRAL AMERICA ON SUNDAY.


I guess we should ignore this......
Don't forget this key word. SHOULD, not WILL.
Member Since: October 9, 2008 Posts: 0 Comments: 8399
Maybe since there saying possible south Florida maybe that means central Florida? since the last time I heard Central Florida was going to get nasty weather that meant southern Florida. lol
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Quoting Skyepony:
Oceansat caught 97L.. Pulling together nicely, a little elongated still, but gonna hit land if it doesn't move N.

Satelite picture shows that is moving apparently NNW to NW ...so is likely will skip land.
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Quoting luvtogolf:


The NHC is the last TWO said it was drifting Northward.
I know but some people are saying it looks like it is moving west.
Member Since: October 9, 2008 Posts: 0 Comments: 8399
What will the % of 96L be at 8pm EST , I say 60-70%!
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Quoting jrweatherman:
FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

THE AREA OF LOW PRESSURE IN THE SOUTHWESTERN CARIBBEAN SEA IS NOW LOCATED A LITTLE BIT LESS THAN 100 MILES NORTHEAST OF SAN ANDRES ISLAND. THE LOW IS CURRENTLY DRIFTING NORTHWARD...BUT STRONG HIGH PRESSURE TO THE NORTH SHOULD FORCE THE LOW TO MOVE TOWARD CENTRAL AMERICA ON SUNDAY.


I guess we should ignore this......

I don't understand where Avila gets that from...Steering currents are very weak, and high pressure centered over Central America would definitely not allow for 96L to move in that direction.

So, yeah, despite them being the experts, I'd ignore that. We'll probably see different wording at 8PM.
Member Since: July 6, 2010 Posts: 113 Comments: 32335
FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

THE AREA OF LOW PRESSURE IN THE SOUTHWESTERN CARIBBEAN SEA IS NOW LOCATED A LITTLE BIT LESS THAN 100 MILES NORTHEAST OF SAN ANDRES ISLAND. THE LOW IS CURRENTLY DRIFTING NORTHWARD...BUT STRONG HIGH PRESSURE TO THE NORTH SHOULD FORCE THE LOW TO MOVE TOWARD CENTRAL AMERICA ON SUNDAY.


I guess we should ignore this......
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Quoting bohonkweatherman:
La Nina continues to kick South Central Texas in the Butt, LOL. FIRE WEATHER...
RECENT TRENDS TOWARD A DRIER FRONTAL PASSAGE ON THURSDAY ARE
PRESENTING THE POTENTIAL FOR CRITICAL OR NEAR-CRITICAL FIRE
WEATHER CONDITIONS...ESPECIALLY ACROSS THE WESTERN HALF OF SOUTH
CENTRAL TEXAS. A COUPLE OF VERY DRY DAYS WILL FOLLOW THE FROPA
LATE NEXT WEEK.

That mid/late-week front looks like a solid one with which to close out October. The Tuesday high in Oklahoma City is 84, while on Wednesday it's 59; in Topeka, it's 76 then 53; in Amarillo it's 81 then 52. And it's pretty much the same story throughout the region--and, as your comment indicates, there's only a slightly elevated chance of showers during the frontal passage; it's gonna be a dry one.

Sorry about that...
Member Since: November 8, 2009 Posts: 4 Comments: 13579

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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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