Hurricane Irma Discussion Number 40
NWS National Hurricane Center Miami FL AL112017
1100 PM EDT Fri Sep 08 2017
An Air Force Hurricane Hunter flight has found that Irma has
re-intensified to category 5 strength. The plane measured a
maximum flight-level wind of 154 kt and SFMR winds of 140-145 kt in
the northwestern eyewall, so the initial intensity is raised to 140
kt. The hurricane is producing very deep convection in all
quadrants around the eye, which the Air Force flight measured to be
35 n mi wide.
一架空军飓风猎人机已发现Irma已重新增强为第五级强度. 此机测得
154节最大飞行高度风与在眼墙西北侧140-145节的SFMR风风速
因此现行强度提升为140节.
此飓风正在风眼四周全象限产生非常深的对流,空军机测量得出35海里宽
Apparently the ridge to the north of Irma has been stronger than
expected, and the initial motion remains westward, or 280/11 kt.
The track guidance continues to insist on Irma turning
west-northwestward soon, moving along the Cuban Keys adjacent to
the north coast of Cuba during the next 24 hours. After that time,
Irma is expected to turn sharply north-northwestward and accelerate
after 48 hours, moving parallel to the west coast of Florida and
then into Georgia. Mainly because Irma's eye has not deviated from
its westward motion, the new NHC forecast track has again shifted
slightly westward. Because of the hurricane's angle of approach to
the west coast of Florida, it is extremely difficult to pinpoint
exactly where the center might move onshore.
显然的在Irma北边的高压脊比预期地要强,现行运动维持西行, 280度/11节
路径指引持续坚持在二十四小时内Irma很快转向西北西,沿着邻近古巴礁岛到古巴北海岸
此时间之后, 在四十八小时后Irma预期急转北北西并加速,沿着佛州西海岸平行移动
并进入乔治亚州
主要因Irma风眼尚未偏离西向运行, 本中心新路径预报再次稍微向西调整.
因为飓风的靠近角度靠向佛州西海岸, 这很非常困难去推定中心会向海岸何处实际移动
If the eye continues to move over the Cuban Keys and does not move
inland over the main island of Cuba, then Irma would likely not
lose much intensity during the next day or so. As we've stated
many times, fluctuations in intensity are likely during the next 36
hours due to possible and unpredictable eyewall replacement cycles.
After 36 hours, there are some indications that vertical shear may
increase over the hurricane, and a little more weakening is
anticipated at that time. Because of the concerns in the track
forecast noted above, Irma would be able to maintain a strong
intensity for a longer period of time if the center stays off the
west Florida coast. Regardless, Irma is still expected to be a
dangerous hurricane as it approaches the Florida Keys and the west
coast of Florida through 48 hours.
假如风眼持续在古巴礁岛移动并不进入古巴岛陆地, 那Irma应该在数日内
不太可能损失太多强度. 我们已强调很多次, 因无法预期的眼墙置换有可能会发生
强度有可能在接下来三十六小时内变动
在三十六小时后, 有些指示垂直风切也许会在飓风外增强, 预期在这时间点许些减弱
因在上述路径预报中有这顾虑, 如果中心停留在佛州西海岸,
Irma应该可以维持强力的强度较长一段时间
无论如何, Irma仍预计是个危险的飓风,
在四十八小时前往佛州礁岛群与佛州西海岸
(Message Keys与前报相同)