Monthly Weather Summary PDF Print E-mail


Monthly Weather Summary





Relatively moist conditions prevailed at low levels of the atmosphere at the start of the month of October with a relatively dry and subsident pattern at the upper levels. A rather slack pressure gradient supported light surface winds and coastal convergence over-night and resulted in a few early morning showers along the coast shifting to inland areas during the daytime. Highest rainfall amounts of 23.4mm was recorded at Big Falls. Mainly fair and dry conditions prevailed during the Thursday 2nd and Friday 3rd as an east-southeasterly flow developed at the surface and low levels to accompany a weakly convergent pattern aloft. As a tropical wave approached by Satursday 4th low leval winds backed to the northeast and supported isolated night-time showers and small rainfall amounts mainly over the south and coast. The tropical wave crossed the area by Saturday 5th and winds veered to the east. However, a ridge from the west supported a weakly convergent northwesterly flow aloft and only a few light showers occurred in a diurnal pattern over southern areas. Mainly fair weather with isolated prevailed during the 6th as a southeasterly flow developed.


A very wet pattern developed during Tuesday 7th through Friday 24th. Showers and thunderstorms affected the central and southern areas of the country during Tuesday 7th as winds at the surface and low levels backed to the northeast. Low level moisture increased as a tropical wave accompanied by a low over the southwest Caribbean approached the area. A moist southwesterly flow prevailed aloft between a trough over the Gulf of Mexico and ridge over the Caribbean. The tropical wave crossed the country during Wednesday 8th and encountered the unstable upper level conditions. However, the flow continued northeasterly as another tropical wave approached in quick succession and crossed the country during the night of Friday 10th into early morning Saturday 11th. The surface and low level flow continued northeasterly as a trough exyended over the Northwest Caribbean and coastal waters through the Yucatan Channel. At upper levels the ridge shifted west of our area and the flow became northwesterly.


The surface flow veered to the east during Saturday 12th and east-southeast during Sunday 13th due to a deepening frontal low over Texas. A pre-frontal trough moved across northwestern Yucatan by Monday 14th as the cold front moved over the Bay of Campeche and stalled. The associated continental high moved across the Gulf of Mexico during Thursday 16th and the flow became east-northeasterly. A broad monsoon type flow would developed across Central America and the western Caribbean during the next few days as the monsoon trough was pulled north along the Pacific coast of Central America. A deep layer southeasterly to southerly flow dominated the low levels with west-southwesterly to westerly flow at the upper levels as a high / ridge extended east over the area. The pattern supported deep layer moisture at all levels. A developing 1009hPa low developed along the tail end of the stalled front over the western Bay of Campeche by Monday 20th and deepened to 1002hPa by Wednesday 22nd before developing into Tropical Depression #9 while maintaining the moist southeasterly flow over our area. A trough / ridge pattern provided a diffluent / divergent pattern aloft. By Thursday 23rd the remnant low from TD#9 moved across Yucatan to northern Guatemala and Belize, then over the northwest Caribbean by Saturday 25th where it weakened to an open trough / wave.


A cold front crossed the country during Saturday 25th and high pressure influence at the surface along with dry air aloft supported mainly fair, windy and cool weather through Monday 27th as the tail end of the front merged with the remnant trough from TD#9 to yield a 1008hPa over northeastern Honduras / Nicaragua. During the early morning of Monday 27th the low was upgraded to Tropical storm Hanna then downgraded to a depression with a trough north across the northwestern Caribbean by 00z Tuesday 28th.


Moisture associated with this systen mover back over our area in a northeasterly flow as the remnant low moved inland over Honduras and weakened as a meso-scale swirl emerged near the Bay Islands as a more pronounced center of circulation. A surface trough and moist northeasterly airflow perisited across the northwestern Caribbean Sea the next few days. A cold front then crossed the Gulf of Mexico to position just north of Yucatan by Friday 31st with the associated continental high maintaining the north-northeasterly flow and relatively moist conditions over our area.       



M.  Gentle.