颶風古斯塔夫-21 - 颱風討論

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WTNT42 KNHC 300301
TCDAT2
HURRICANE GUSTAV DISCUSSION NUMBER 21
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL072008
1100 PM EDT FRI AUG 29 2008

REPORTS FROM AIR FORCE RESERVE AND NOAA HURRICANE HUNTER AIRCRAFT
SHOW THAT GUSTAV HAS A 25 NM WIDE EYE THAT IS BECOMING BETTER
DEFINED IN RECENT SATELLITE IMAGERY. RECENT TRMM AND SSM/I IMAGERY
ALONG WITH CUBAN RADAR DATA SUGGESTS THAT AN OUTER EYEWALL WITH A
DIAMETER OF ABOUT 100 N MI IS FORMING...AND THE NOAA PLANE REPORTED
88 KT FLIGHT-LEVEL WINDS AT 770 MB IN THE CORRESPONDING OUTER WIND
MAXIMUM. RELIABLE-LOOKING DATA FROM THE SFMR SHOWS 65-70 KT
SURFACE WINDS IN BOTH THE INNER AND OUTER WIND MAXIMA...BUT THE
HURRICANE FORCE WINDS ARE CURRENTLY CONFINED TO THE NORTHEASTERN
QUADRANT. THE INITIAL INTENSITY IS SET TO 70 KT IN AGREEMENT WITH
THE AIRCRAFT DATA.

從空軍備役和本署的颶風獵人機報告顯示出古斯塔夫有個二十五海浬寬的風眼,並清楚
在現在的衛星影像中. 現行的TRMM和SSM/I影像順著古巴的雷達推測有一個
直徑達一百海里的外層眼牆正形成中...以及本署的飛機報出在七七零毫巴的八十八節
飛行高度風相當於外圍風速最大值. 從SFMR可靠的觀測資料展現出內部和外部一起的
表面風速最大值有六十五~七十節... 但是颶風風力現受限於東北象限. 現行強度和
飛機資料一致設定於七十節

THE INITIAL MOTION IS 305/9. THERE IS NO CHANGE TO THE FORECAST
PHILOSOPHY FROM THE PREVIOUS PACKAGE...WITH GUSTAV EXPECTED TO MOVE
GENERALLY NORTHWESTWARD ON THE SOUTHWEST SIDE OF A LOW/MID-LEVEL
RIDGE OVER THE EASTERN UNITED STATES. THERE HAS ALSO BEEN LITTLE
CHANGE IN THE GUIDANCE...WITH SOME CONTINUING DISAGREEMENT ON HOW
MUCH RIDGING WILL EXTEND WESTWARD TO THE NORTH OF GUSTAV AND HOW
GUSTAV WILL INTERACT WITH AN UPPER-LEVEL TROUGH OVER THE GULF OF
MEXICO. THE GUIDANCE IS TIGHTLY CLUSTERED THROUGH 48 HR AND THEN
SHOWS SOME SPREAD. THE GFDL REMAINS ON THE EASTERN SIDE OF THE
GUIDANCE ENVELOPE AND CALLS FOR LANDFALL IN SOUTHEASTERN
LOUISIANA...WHILE THE UKMET CALLS FOR A WESTWARD TURN AND LANDFALL
ON THE MIDDLE TO UPPER TEXAS COAST. THE REMAINDER OF THE GUIDANCE
LIES BETWEEN THESE EXTREMES. THE NEW FORECAST TRACK IS AN UPDATE
OF THE PREVIOUS FORECAST FOR THE FIRST 72 HR...THEN IS SLOWER AND A
LITTLE TO THE LEFT OF THE PREVIOUS FORECAST THEREAFTER. IT LIES IN
THE EASTERN SIDE OF THE GUIDANCE ENVELOPE.

現行運動為三零五度/九浬. 從之前的PACKAGE這裡沒有對預報的觀點做出改變...
古斯塔夫預期在美國東部上空的低/中層脊的東南側作正西北西移動.
指引中同樣地有點變化... 在脊會向西延伸多少到古斯塔夫的北邊
以及古斯塔夫怎樣和在墨西哥灣的高層槽做出互動有一些連續的不一致
四十八小時內的指引緊密地聚群的然後就顯示出一些分散. GFDL依然在指引外殼東側並
報出在路易斯安納東南方登陸... 而UKMET報出向西轉向以及在上德州海岸中間登陸.
其餘的指引在這些極端情形之間. 新的針對最初七十二小時的官方路徑是前次預報的更新
.
於是變慢之後比前次預報有點向左. 這伸展在指引外殼的東側

THE INTENSITY FORECAST REMAINS PROBLEMATIC. WHILE GUSTAV HAS GOOD
OUTFLOW IN ALL QUADRANTS...WATER VAPOR IMAGERY SUGGESTS WESTERLY
FLOW ASSOCIATED WITH THE GULF OF MEXICO TROUGH UNDERCUTTING THE
OUTFLOW. THIS...COMBINED WITH THE CONCENTRIC WIND MAXIMA...MAY BE
SLOWING INTENSIFICATION. GUSTAV IS OVER WARM WATER WITH HIGH
OCEANIC HEAT CONTENT...AND SHOULD REMAIN OVER SUCH WATER UNTIL IS
PASSES NORTH OF THE LOOP CURRENT IN 48-60 HR. THUS...THERE IS A
DISTINCT POSSIBILITY OF RAPID INTENSIFICATION IF THE STORM
STRUCTURE AND THE INTERACTION WITH THE TROUGH PERMIT. THE SHIPS
MODEL CALLS FOR A PEAK INTENSITY OF 104 KT...THE LGEM 97 KT...THE
HWRF 114 KT...THE FLORIDA STATE SUPERENSEMBLE 114 KT...AND THE GFDL
129 KT. BASED ON THIS AND THE PREMISE THAT THE INTERACTION WITH
THE TROUGH WILL ALLOW STEADY STRENGTHENING...THE FORECAST PEAK
INTENSITY IS INCREASED TO 115 KT. GUSTAV COULD GET STRONGER THAN
THAT IF RAPID INTENSIFICATION OCCURS. THE INTENSITY FORECAST SHOWS
A SLIGHT WEAKENING AT 72 HR AS GUSTAV REACHES LOWER OCEANIC HEAT
CONTENT AND POSSIBLE ENCOUNTERS SOME WESTERLY SHEAR. HOWEVER...
GUSTAV IS EXPECTED TO MAKE LANDFALL AS A MAJOR HURRICANE. THE
FINAL [FLY IN THE OINTMENT] IS THE POSSIBILITY OF EYEWALL REPLACEMENT
CYCLES... WHICH COULD SIGNIFICANTLY AFFECT THE INTENSITY.

強度預報依然很問題重重. 儘管古斯塔夫全象限有優良的OUTFLOW...水氣影像推測
與位於墨西哥灣的槽組合的向西流動切入OUTFLOW底層. 這樣地...和同心風最大值
結合... 也許會弱化增強. 古斯塔夫位於含有高海洋含量的溫暖水域... 以及依然在這樣
的水域直到四十八~六十小時間通過墨西哥灣套流. 因此...如果風暴結構和與槽互動許可
,
此處RAPID INTENSIFICATION有明顯的可能性(出現).
SHIPS模型報出一零四節尖峰強度... LGEM九十七節... HWRF一一四節 ...
(佛羅里達大學的)SUPERENSEMBLE 一一四節... 以及GFDL一二九節.
根據此數據和以槽互動的前提將會允許穩定的增強...預報尖峰強度已增加到一一五節.
假如RAPID INTENSIFICATION出現了古斯塔夫能比預報中更強. 強度預報顯示出
在七十二小時後當古斯塔夫抵達低海洋熱含量並有可能遭遇一些向西風切就會輕微的減弱
.
然而... 古斯塔夫預期以主要颶風身份登陸. 最後的[瑕疵]是眼牆置換循環的可能性...
這個可能在相當大的程度上影響颶風的強度

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Geheimer Wetter- und Seeschlüssel der Kriegsmarine
Teil 2
Watterkurzschlüssel (3 Auflage)

Oberkommando de Kriegsmarine Berlin 1942


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