http://www.explainxkcd.com/wiki/index.php/1126

Transcript

Tuesday, November 29th, 2005: Tropical Storm Epsilon … The 26th named storm of the apparently never ending 2005 Atlantic hurricane season.

10 PM Wed: The window of opportunity for strengthening should close in 12-24 hr. 4 PM Thu: Slow but steady weakening is expected to begin in 12-24 hours.

4 AM Fri: Epsilon does not appear weaker. 10 AM Fri: Epsilon has been upgraded to a 65-kt hurricane.

4 PM Sat: Epsilon has continued to strengthen against all odds … [but] can not maintain the current intensity much longer since the environment is becoming increasingly unfavorable.

10 PM Sat: Epsilon might or might not still be a hurricane … but in any case it likely will not be one on Sunday. 4 AM Sun: Epsilon is downgraded to a tropical storm.

10 AM Sun: Morning satellite images indicate that Epsilon has restrengthened.

There are no clear reasons … and I am not going to make one up … to explain the recent strengthening of Epsilon and I am just describing the facts. However … I still have to make an intensity forecast and the best bet at this time is to predict weakening … Epsilon will likely become a remnant low. I heard that before about epsilon … haven’t you?

4 PM Mon: The cloud pattern continues to be remarkably well-organized for a hurricane at such high latitude in December.

10 PM Mon: We have said this before … but Epsilon really does not appear as strong this evening as it did this afternoon.

4 AM Tue: I have run out of things to say.

10 PM Tue: The end is in sight. It really really is. But in the meantime … Epsilon continues to maintain hurricane status. 4 AM Wed: The end is in sight … yes … but not quiet yet. I thought I was going to find a weakening system and instead I found that Epsilon is still a hurricane.

10 AM Thu: Convection has vanished and Epsilon is now a tight swirl of low clouds. I hope this is the end of the long lasting 2005 hurricane season.

NOPE.

Friday, December 30th, 2005: An elongated area of low pressure … which had its origins in an old frontal trough … began developing organized convection overnight. Advisories are initiated on the 27th tropical storm of 2005.

4PM Fri: Although the atmosphere seems to want to develop tropical storms ad nauseam … the calendar will shortly put an end to the use of the Greek alphabet to name them.

10 PM Sat: Zeta appeared on the verge of losing all of its deep convection a few hours ago … but since about 21z the convection has been on somewhat of an increase again.

10 PM Sun: This is like Epsilon all over again. Most of the conventional guidance suggested that zeta should have been dissipated by now … well … zeta is pretty much alive at this time. I have no choice but to forecast weakening again and again.

4 AM Mon: By 24-36 hours … a significant increase in westerly winds … should act to shear away most of the associated convection … and finally bring the 2005 Atlantic hurricane season to a merciful ending. 4 PM Mon: It is hard to conceive that a tropical cyclone will be able to survive for very long in such a hostile environment. therefore I have not backed off on the forecast of weakening.

10 PM Mon: Zeta is stronger than yesterday. 10 AM Wed: As you can see… I ran out of things to say.

4 AM Thu: Satellite intensity estimates have decreased. Zeta is downgraded to a 30 kt tropical depression.

10 AM Thu: Shortly after the previous advisory had been issued … regretfully … the intensity … increased to 35 kt and Zeta is a tropical storm once again.

10 PM Thu: Although it seems as if Zeta will never die … the forecast continues to show weakening.

4 PM, Friday, January 6, 2006: Zeta no longer meets the criteria of a tropical cyclone… which means that both it and the 2005 Atlantic hurricane season have ended. This is the national hurricane center signing off for 2005.

[The bald man still sits at his desk, the man with hair is no longer in his chair.]

[Again, we see the bald man at his desk and the other guy’s empty desk.]
Bald guy: Actually, Zeta’s cloud pattern is…
Hair guy: (out of panel) NO.
Bald guy: Ok.

I posted the above to sci.geo.earthquakes and then thought I had better grab the archived advisories before they get doctored. Not that I believe they will.

There are a lot of them and it is all in shouting because that is the way that faxes worked originally.
I will put them in the comments in chronological order as they were linked to in the original comic:
http://xkcd.com/1126/

2 thoughts on “http://www.explainxkcd.com/wiki/index.php/1126

  1. The first advisory looks like this:
    Tropical Storm EPSILON

    ZCZC MIATCDAT4 ALL
    TTAA00 KNHC DDHHMM
    TROPICAL STORM EPSILON DISCUSSION NUMBER 1
    NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
    10 AM EST TUE NOV 29 2005

    CONVENTIONAL SATELLITE IMAGERY…NEARBY SHIP AND BUOY OBSERVATIONS
    …AND 29/0938Z QUIKSCAT SATELLITE WIND DATA INDICATE THE LARGE
    NON-TROPICAL LOW PRESSURE SYSTEM LOCATED ABOUT 730 NMI EAST OF
    BERMUDA HAS ACQUIRED ENOUGH CONVECTION NEAR THE CENTER TO BE
    CLASSIFIED AS TROPICAL STORM EPSILON…THE 26TH NAMED STORM OF THE
    APPARENTLY NEVER ENDING 2005 ATLANTIC HURRICANE SEASON. THE INITIAL
    INTENSITY OF 45 KT IS BASED ON BLEND OF 40-KT QUIKSCAT WINDS IN THE
    NORTHWEST QUADRANT AND A 29/0800Z 996.0 MB…EQUAL TO APPROXIMATELY
    55 KT… PRESSURE REPORT FROM BUOY 41543 THAT WAS LOCATED ABOUT 90
    NMI SOUTH OF THE CENTER.

    THE INITIAL MOTION ESTIMATE IS 270/07 KT. EPSILON IS EXPECTED TO
    MOVE GENERALLY WESTWARD FOR THE NEXT 24-36 HOURS AROUND THE
    SOUTHERN PERIPHERY OF A HIGH-LATITUDE RIDGE. AFTER THAT…THE
    CYCLONE IS FORECAST TO SLOW DOWN AND TURN AND NORTHEASTWARD AS A
    DEEP-LAYER TROUGH AND ASSOCIATED FRONTAL SYSTEM CURRENTLY OVER THE
    EASTERN UNITED STATES MOVES EASTWARD AND BEGINS TO TURN EPSILON
    BACK TOWARD THE EAST. BY 96 HOURS… EPSILON IS EXPECTED TO
    ACCELERATE RAPIDLY NORTHEASTWARD AND BECOME EXTRATROPICAL OR
    POSSIBLY EVEN BECOME ABSORBED BY THE MUCH LARGER EXTRATROPICAL LOW
    PRESSURE SYSTEM. THE FORECAST TRACK IS SIMILAR TO THE NHC MODEL
    CONSENSUS.

    EPSILON IS LOCATED OVER 25C SSTS… WHICH IS SUFFICIENTLY WARM
    ENOUGH TO SUPPORT AT LEAST MINIMAL HURRICANE INTENSITY. ALTHOUGH A
    BANDING EYE-LIKE FEATURE DURING THE PAST COUPLE OF HOURS… THE
    LOW-LEVEL PRESSURE AND WIND FIELDS APPEAR TO MORE REPRESENTATIVE OF
    SLOW DEVELOPING SUBTROPICAL CYCLONES. AS SUCH… INTENSIFICATION IS
    EXPECTED TO BE SLOWER THAN USUAL. HOWEVER… IF THE DEEP CONVECTION
    CONTINUES TO RAPIDLY INCREASE AROUND THE CENTER… THEN MORE AND
    EARLIER STRENGTHENING COULD OCCUR THAN WHAT IS FORECAST. THE
    OFFICIAL INTENSITY FORECAST CLOSELY FOLLOWS THE SHIPS MODEL AND IS
    HIGHER THAN THE GFDL MODEL.

    FORECASTER STEWART

    FORECAST POSITIONS AND MAX WINDS

    INITIAL 29/1500Z 31.6N 50.4W 40 KT
    12HR VT 30/0000Z 31.7N 51.7W 50 KT
    24HR VT 30/1200Z 31.8N 53.4W 55 KT
    36HR VT 01/0000Z 32.0N 54.3W 60 KT
    48HR VT 01/1200Z 32.7N 53.7W 60 KT
    72HR VT 02/1200Z 33.5N 51.0W 55 KT
    96HR VT 03/1200Z 35.0N 45.5W 50 KT…BECOMING EXTRATROPICAL
    120HR VT 04/1200Z 37.0N 41.0W 45 KT…EXTRATROPICAL

    ***

    I put it in text editor with a copy and paste then got rid of line ends by replacing the regular expression:
    \n
    with a simple space character and then looked for two space characters and replaced them with two line end expressions (\n\n) to get the following:

    ***

    Tropical Storm EPSILON

    ZCZC MIATCDAT4 ALL TTAA00 KNHC DDHHMM TROPICAL STORM EPSILON DISCUSSION NUMBER

    1 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 10 AM EST TUE NOV 29 2005

    CONVENTIONAL SATELLITE IMAGERY…NEARBY SHIP AND BUOY OBSERVATIONS …AND 29/0938Z QUIKSCAT SATELLITE WIND DATA INDICATE THE LARGE NON-TROPICAL LOW PRESSURE SYSTEM LOCATED ABOUT 730 NMI EAST OF BERMUDA HAS ACQUIRED ENOUGH CONVECTION NEAR THE CENTER TO BE CLASSIFIED AS TROPICAL STORM EPSILON…THE 26TH NAMED STORM OF THE APPARENTLY NEVER ENDING 2005 ATLANTIC HURRICANE SEASON. THE INITIAL INTENSITY OF 45 KT IS BASED ON BLEND OF 40-KT QUIKSCAT WINDS IN THE NORTHWEST QUADRANT AND A 29/0800Z 996.0 MB…EQUAL TO APPROXIMATELY 55 KT… PRESSURE REPORT FROM BUOY 41543 THAT WAS LOCATED ABOUT 90 NMI SOUTH OF THE CENTER.

    THE INITIAL MOTION ESTIMATE IS 270/07 KT. EPSILON IS EXPECTED TO MOVE GENERALLY WESTWARD FOR THE NEXT 24-36 HOURS AROUND THE SOUTHERN PERIPHERY OF A HIGH-LATITUDE RIDGE. AFTER THAT…THE CYCLONE IS FORECAST TO SLOW DOWN AND TURN AND NORTHEASTWARD AS A DEEP-LAYER TROUGH AND ASSOCIATED FRONTAL SYSTEM CURRENTLY OVER THE EASTERN UNITED STATES MOVES EASTWARD AND BEGINS TO TURN EPSILON BACK TOWARD THE EAST. BY 96 HOURS… EPSILON IS EXPECTED TO ACCELERATE RAPIDLY NORTHEASTWARD AND BECOME EXTRATROPICAL OR POSSIBLY EVEN BECOME ABSORBED BY THE MUCH LARGER EXTRATROPICAL LOW PRESSURE SYSTEM. THE FORECAST TRACK IS SIMILAR TO THE NHC MODEL CONSENSUS.

    EPSILON IS LOCATED OVER 25C SSTS… WHICH IS SUFFICIENTLY WARM ENOUGH TO SUPPORT AT LEAST MINIMAL HURRICANE INTENSITY. ALTHOUGH A BANDING EYE-LIKE FEATURE DURING THE PAST COUPLE OF HOURS… THE LOW-LEVEL PRESSURE AND WIND FIELDS APPEAR TO MORE REPRESENTATIVE OF SLOW DEVELOPING SUBTROPICAL CYCLONES. AS SUCH… INTENSIFICATION IS EXPECTED TO BE SLOWER THAN USUAL. HOWEVER… IF THE DEEP CONVECTION CONTINUES TO RAPIDLY INCREASE AROUND THE CENTER… THEN MORE AND EARLIER STRENGTHENING COULD OCCUR THAN WHAT IS FORECAST. THE OFFICIAL INTENSITY FORECAST CLOSELY FOLLOWS THE SHIPS MODEL AND IS HIGHER THAN THE GFDL MODEL.

    FORECASTER STEWART

    FORECAST POSITIONS AND MAX WINDS

    INITIAL

    29/1500Z 31.6N

    50.4W

    40 KT

    12HR VT

    30/0000Z 31.7N

    51.7W

    50 KT

    24HR VT

    30/1200Z 31.8N

    53.4W

    55 KT

    36HR VT

    01/0000Z 32.0N

    54.3W

    60 KT

    48HR VT

    01/1200Z 32.7N

    53.7W

    60 KT

    72HR VT

    02/1200Z 33.5N

    51.0W

    55 KT

    96HR VT

    03/1200Z 35.0N

    45.5W

    50 KT…BECOMING EXTRATROPICAL 120HR VT

    04/1200Z 37.0N

    41.0W

    45 KT…EXTRATROPICAL

    ***

    Clearly needs some work but apart from leaving the final forecast alone, I can live with it.

    This is the final forecast part, restored:
    ***
    FORECAST POSITIONS AND MAX WINDS

    INITIAL 29/1500Z 31.6N 50.4W 40 KT
    12HR VT 30/0000Z 31.7N 51.7W 50 KT
    24HR VT 30/1200Z 31.8N 53.4W 55 KT
    36HR VT 01/0000Z 32.0N 54.3W 60 KT
    48HR VT 01/1200Z 32.7N 53.7W 60 KT
    72HR VT 02/1200Z 33.5N 51.0W 55 KT
    96HR VT 03/1200Z 35.0N 45.5W 50 KT…BECOMING EXTRATROPICAL
    120HR VT 04/1200Z 37.0N 41.0W 45 KT…EXTRATROPICAL
    ***
    I will do the lot again changing the case and leaving the final forecasts alone.

  2. tROPICAL sTORM epsilon

    zczc miatcdat4 all ttaa00 knhc ddhhmm tropical storm epsilon discussion number

    1 nws tpc/national hurricane center miami fl 10 am est tue nov 29 2005

    conventional satellite imagery…nearby ship and buoy observations …and 29/0938z quikscat satellite wind data indicate the large non-tropical low pressure system located about 730 nmi east of bermuda has acquired enough convection near the center to be classified as tropical storm epsilon…the 26th named storm of the apparently never ending 2005 atlantic hurricane season. the initial intensity of 45 kt is based on blend of 40-kt quikscat winds in the northwest quadrant and a 29/0800z 996.0 mb…equal to approximately 55 kt… pressure report from buoy 41543 that was located about 90 nmi south of the center.

    the initial motion estimate is 270/07 kt. epsilon is expected to move generally westward for the next 24-36 hours around the southern periphery of a high-latitude ridge. after that…the cyclone is forecast to slow down and turn and northeastward as a deep-layer trough and associated frontal system currently over the eastern united states moves eastward and begins to turn epsilon back toward the east. by 96 hours… epsilon is expected to accelerate rapidly northeastward and become extratropical or possibly even become absorbed by the much larger extratropical low pressure system. the forecast track is similar to the nhc model consensus.

    epsilon is located over 25c ssts… which is sufficiently warm enough to support at least minimal hurricane intensity. although a banding eye-like feature during the past couple of hours… the low-level pressure and wind fields appear to more representative of slow developing subtropical cyclones. as such… intensification is expected to be slower than usual. however… if the deep convection continues to rapidly increase around the center… then more and earlier strengthening could occur than what is forecast. the official intensity forecast closely follows the ships model and is higher than the gfdl model.

    forecaster stewart
    ***
    Clearly Linux could use some work with the change case mod.
    But it is better than shouting.

    I’ll be babysitting today, maybe I can use the computer he’s got. He uses Microsoft.

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