Seasonal Forecast: August to October 2022

Date of Issue: August 15th, 2022

Forecast

  • Rainfall
    • There is medium to high confidence that rainfall accumulation is likely to be as high as or possibly even more than usual, as we move into the heart of the wet season
    • On average, hurricane season activity continues to increase during this period coming to a peak in September
    • A notable increase in the number of wet days and 7-day wet spells is likely which will increase flood potential across the island
    • A likely increase in 3-day extreme wet spells may increase the chance (moderate to high) of flash floods and associated hazards particularly towards September
    • Usual rainfall amounts are projected for the November to January season
    • At this time, there is no concern for drought conditions
  • Temperature:
    • The region is well into the heat season which peaks in October
    • Day and night-time temperatures are likely to be as warm as usual
    • Heat stress is likely to increase due to higher humidity and lighter winds

Influencing Factors

  • El Niño Southern Oscillation (ENSO)
    • Recent observations: Sea Surface Temperatures (SSTs) in the eastern Pacific remain below normal (-0.6°C); La Niña conditions exists
    • Model forecast and guidance: Models forecast indicate that La Niña may persist through August to October (ASO) and into November to January (NDJ) (60-55% confidence).
    • Expected impacts on rainfall and temperatures: La Niña tilts the odds to more rainfall activity during the wet season and the transition into the dry season. La Niña also increases the chance of tropical cyclone formation
  • Climate conditions in the Tropical North Atlantic (TNA) and the Caribbean Sea
    • Recent observations: Warmer than usual SSTs persisted to 1°C above average around the northern section of the Caribbean Sea and in the sub-tropical portions of the North Atlantic in June. Elsewhere in the Caribbean SSTs were near normal
    • Expected conditions: Models are forecasting SST to maintain anomalously warm (up to 0.5°C above average) around the Caribbean and in the sub-tropical North Atlantic
    • Expected impacts: Warm SSTs in and around the Caribbean tend to contribute to higher air temperatures with above-average humidity, seasonal rainfall totals and an increased frequency of extreme rainfall

See table below with Climatological Normal/ Averages

August-September-October
CLIMATOLOGICAL NORMAL (30YEARS)
Rainfall Canefield Airport Douglas-Charles Airport
Normal 507.1 to 733.5mm 708.6 to 964.8mm
Wet Days Normal 52 to 64 days 56 to 69 days
7-day Wet Spells Normal 4 to 7 3 to 7
TEMPERATURE (15YRS AVERAGES)
Average Maximum 32.0°C to 32.5°C 31.0°C to 31.4°C
Average Mean 27.9°C to 28.2°C 27.5°C to 27.8°C
Average Minimum 23.8°C to 24.1°C 24.1°C to 24.3°C