Meteorological history Hurricane Alex (2010)

map plotting track , intensity of storm, according saffir–simpson scale

the weather system hurricane alex developed first discernible disturbance in intertropical convergence zone (itcz) on june 17, 2010. on next few days, of associated thunderstorm activity embedded within itcz. national hurricane center (nhc) first mentioned candidate tropical cyclone formation on june 20, while crossing windward islands southeastern caribbean sea; @ time, upper-level wind shear present, leading conditions marginally favorable development. system moved through caribbean, , on june 21, developed extent nhc assessed 50% chance of development tropical depression within 48 hours. next day, however, feature deteriorated thunderstorm activity spread across greater antilles, although upper-level regime remained favorable eventual redevelopment.

on june 24, low-level circulation had gradually become better established south of jamaica, although displaced poorly organized convection. 1800 utc, surface low-pressure area had formed 105 miles (165 km) northeast of cabo gracias dios, nicaragua, due lack of persistent thunderstorm activity, not yet considered tropical cyclone. later day, convection increased on center of circulation, , atmospheric pressures dropped across region. late on june 25, hurricane hunters verified development of surface low pressure area, which, combined increase of thunderstorm activity, indicated system tropical depression. accordingly, cyclone classified tropical depression 1 @ 2200 utc, while located 345 miles (555 km) east-southeast of chetumal, quintana roo. after end of hurricane season, national hurricane center revised analysis , estimated system had become tropical depression @ around 1800 utc. @ time of formation, depression moving west-northwest, steered high pressure system on northern gulf of mexico. anticyclone positioned on storm created environment of minimal wind shear, , depression intensified. @ 0900 utc on june 26, obtained tropical storm status , given name alex.

as tropical storm alex progressed through western caribbean sea towards yucatán peninsula, developed large field of clouds accompanied well-established outflow throughout circulation. inner structure disorganized, although late on june 26, became better defined. @ 2100 utc, tropical storm approached belize coast, hurricane hunters flight reported winds of 65 mph (100 km/h); on june 27, alex made landfall north of belize city @ intensity. upon moving ashore, area of convection increased on center, , convection became better defined crossed yucatán peninsula. while tropical cyclones weaken , become disorganized after landfall, alex seemed become stronger when viewed on radar , satellite imagery—the national hurricane center noted in 1 of forecast discussions cyclone s structure more closely resembled hurricane deteriorating storm. still, after enough time on land, convective activity markedly decreased, , alex weakened tropical depression status approached peninsula s western coastline; although post-analysis determined alex remained minimal tropical storm. late on june 27, storm emerged gulf of mexico large overall convective structure little thunderstorm activity near center due interaction land.

visible satellite image of tropical storm alex near yucatán peninsula

when alex still located on yucatán peninsula, nhc remarked upon potential significant strengthening. because of low wind shear , warm water temperatures in gulf of mexico, possibility existed alex intensify major hurricane—a category 3 storm on saffir-simpson hurricane wind scale—before next landfall. on june 28, thunderstorm activity had reformed on center, , depression re-intensified tropical storm. next day, combination of dry air, increasing wind shear , cooler water temperatures prevented significant convection developing on center. @ same time, alex moving off northwest coast of yucatán peninsula, , environment s conditions became more favorable intensification tropical storm tracked away coast. circulation envelope of alex remained large, , june 29, storm s rainbands covered entire western half of gulf of mexico; rainfall reported along texas , louisiana coasts, while center still several hundred miles offshore. tropical storm continued strengthen, , based on reports hurricane hunters, estimated alex attained hurricane status @ 0300 utc on june 30, 255 miles (415 km) southeast of brownsville, texas.

upon becoming hurricane, alex located in moist, low shear environment, led steady intensification on june 30. pressure continued fall—a sign of intensifying cyclone—with more rapid drop occurring afternoon , evening. hurricane strengthened category 2 storm late on june 30 approached northeastern mexican coast. @ 0200 utc on july 1, alex made landfall @ peak strength, maximum sustained winds of 105 mph (165 km/h), gusts of 125 mph (205 km/h) , unusually low central pressure of 947 millibars (28.0 inhg) in municipality of soto la marina in mexican state of tamaulipas. after storm, national hurricane center revised landfall intensity estimate, showing alex stronger when struck mexican coast, sustained winds of 110 mph (175 km/h) , central pressure of 946 millibars (27.9 inhg). several hours after moving ashore, storm weakened category 1 status, , structure began deteriorate. however, deep convection persisted around center. 1200 utc, alex had weakened tropical storm; 0000 utc july 2, sierra madre oriental disrupted alex s core, causing storm weaken tropical depression , dissipate on san luis potosí. however, interaction mountain range caused orographic lift on eastern side of storm after center of circulation had ceased exist, producing torrential rainfall throughout northern , central mexico. following dissipation of alex, divergence @ 200 mb atmospheric pressure level (approximately @ 10 km (6.2 mi) of altitude), ridge of high pressure located on southern texas, , alex s residual moisture interacted produce intense convection on nuevo león, tamaulipas , coahuila next 72 hours.