The High Pressure System continues to transport dust across the Atlantic Ocean towards the island chain. Also, tropical waves are riding along the southern edge of the Atlantic High Pressure System. The next tropical wave is expected later today followed by a thick patch of dust which could significantly reduce visibility and air quality overnight.
Based on GFS model projections, dust concentrations of PM2.5 could peak near 84µg/m3 while PM10 levels could peak near103 µg/m3 overnight into early morning Tuesday. The presence of the dust and dry air associated with the Saharan Air layer has been limiting showers across our islands. However, a moisture/wind surge ahead of another tropical wave could bring a few scattered showers Tuesday evening into Wednesday.
Fresh (30 - 40 km/h) easterly breeze can be expected this afternoon, becoming occasionally strong (40-50 km/h) by early morning hours. Steady strong breeze can be expected Tuesday night returning to fresh by Wednesday afternoon, briefly flowing from east south-east.
Mean sea-level pressure ranging 1014 - 1016 mb is expected to rise Tuesday to range 1016-1018 mb by evening.
Sea swells are rising in response to the brisk wind flow and moderate to possibly rough (2.4 - 3.0 m) sea swells can be expected by Tuesday afternoon on the east coasts, while moderate (1.8 - 2.4 m) swells can be expected on the west coasts….Advisories are being issued… Wave heights should retreat during Wednesday.
Note: Details on Tropical Storm Aletta and Hurricane Bud is likely to strengthen some more today. Information available at https://www.nhc.noaa.gov/cyclones/.