AmbergrisCaye.com Home Forums Talk Belize Weather Monthly Weather Summaries

Monthly Weather Summary, May 2022

National Meteorological Service of Belize

May marks the end of the 2022 dry season and early May is typically the onset of the rainy season for the Toledo district, which then moves progressively northward with the season starting over most areas by late May and over the entire country by early June. The 2022 rainy season officially started around May 20th in the Corozal and Stann Creek district and in the third dekad of month (21st -30th) over the remainder of the country. Typically, the rainfall during this month is associated with the passage of tropical waves where fifteen waves would cross the country and two upper-level troughs and 4 surface troughs. In May, three tropical waves crossed the country while several surface troughs near to our area produced troughing over the country for most of the month and supported several days of rain in the latter parts of the month. This resulted in rainfall activity being above normal over northern, coastal, and southern locations. It the extreme northwest and western portions of the country, below normal rainfall continues.

During the first week of May, predominantly dry conditions prevailed across the country with moisture capped below 800 hPa and a very dry upper level. Ridging was the overall pattern with slight troughing in the area leading to an east to south-easterly surface flow. As a result, both surface observations and radar images showed isolated showers and thunderstorms for most of the week, with a few showers being observed over some portions of central and southern Belize and over the Maya Mountains due to daytime heating. At the upper levels, a neutral to weakly convergent pattern prevailed for the first half of the week then conditions became weakly divergent in the latter half of the week. An upper-level trough over the western and central Caribbean supported a west to north-westerly upper-level flow which for the most part, hindered the development of significant convection.

Week two marked the beginning of a significant dry spells across most areas of the country due to a strong ridge pattern over the area and limited lower and upper-level moisture. Conditions for most of the week was hot and dry with only isolated showers prevailing. A few areas south and along the coast one day with a few showers or isolated thunderstorms. Thunderstorm activity was concentrated mostly near the western boarder towards the end of the week. The hot and dry conditions were additionally supported by an east to south-easterly airflow over the area from May 8 to 10. The flow shifted to a more east to north-easterly flow from May 11 to 14. The convergent upper-level pattern resulting from a strong west to north-westerly flow due to a trough over the western and southwestern Caribbean provided strong subsidence over our area.

The dry and warm conditions continued into week three with a slack pressure gradient due to weak ridging over the area supporting a light easterly flow through to May 18. Both lower and upper-level moisture remained low during this time and a convergent upper-level pattern persisted. A broad ridge at the upper levels supported a wind shift to a more west to south-westerly flow and towards the end of the week, the upper-level pattern became neutral to weakly divergent as a tropical wave approached the area. The approach of this wave supported an increase in low and upper-level moisture and conditions began to become more unstable over the area. This wave supported a moderate easterly surface flow on May 19 ahead of the wave, and the first tropical wave crossed the country of May 20. The passage of this wave would also mark the beginning of the 2022 rainy season in the north and some areas in southern Stann Creek. For the most part, most of the showery activity was behind the wave and showers or thunderstorms continued isolated over most areas, with a few thunderstorms near the western border.

The moisture from the first tropical wave persisted into week four and continue to the end of the month. Conditions became very moist in both the low and upper levels. For the remainder of the month, the convective potential remained high as a divergent upper-level pattern prevailed with a west to south-westerly wind component due to an upper-level ridge over the area. Near the surface, a light to moderate east to south-easterly flow prevailed. Some showers, a few thunderstorms and periods of rain occurred over most areas of the country during this week, especially along southern, northern, and coastal areas due to the passage of a tropical wave on May 24 and another on May 28 with lingering moisture behind both waves. The most significant rainfall occurred on May 22 near Melinda with 200.1mm of rainfall. The Corozal District had the most rain days with 12, above the normal monthly average of 7 and the overall monthly total was 109% above normal. Stann Creek district received the highest monthly rainfall amount of 386mm in 7 rain days.

The graph and maps below summarize the total rainfall and average maximum and minimum temperatures. They also give an indication of how these readings compare to the normal for the month across the stations sampled. As can be seen, most of the country experienced above normal rainfall, especially along coastal areas while below normal conditions continue to be observed over the western portions of the country. In terms of temperatures, most of the stations sampled show near normal maximum/daytime and minimum/night-time temperatures except for Punta Gorda where slightly cooler than normal minimum temperatures were recorded.

Monthly Rainfall Summary



Monthly Maximum Temperatures



Monthly Minimum Temperatures



Rainfall Observed: May 2022 (mm)



Rainfall Observed: May 2022 (% Above/Below Average)