MOnthly weather bulletin

  JULY 2008

1. SUMMARY

Overall, the country received average to very much above average amounts of rainfall. Majority places had recorded lower temperature than the long-term average value. The country also recorded lower than average amounts of daily solar radiation and experienced lower rates of evaporation.

2. RAINFALL

Generally, Southwest Monsoon is the drier season for most of the places in Malaysia. During this period, the stable atmosphere will reduce the convection activities which lead to the drier and hazy condition especially over urban and the industrial area.

Overall, Peninsular Malaysia experienced wetter condition in July 2008 as compared to the previous month. Most places in peninsula had recorded average to very much above average amount of rainfall. However, there were certain areas in Penang, Kedah, Kelantan as well as Selangor had undergone drier condition with recorded of below average amount of rainfall.

Sabah and Sarawak had experienced more humid than usual weather this July. Both states received average to very much above average amount of rainfall. The rainfall distribution for Sabah was generally influenced by the side effect from the tracked of Typhoon Kalmaegi and Fung-Wong which had developed over the western Pacific Ocean and northern South China Sea. These typhoon tracked had induced the occurrence of strong wind and thunderstorms over coastal area of Sabah during the month.

As for total monthly rainfall, over Peninsular Malaysia; Cameron Highlands recorded the highest total rainfall of 389.8mm where as Petaling Jaya recorded the lowest total rainfall of 66.2mm. In Sarawak, Bintulu recorded the highest total rainfall of 585.8mm while Kuching recorded the lowest total rainfall of 183.5mm. For Sabah, Kota Kinabalu recorded the highest total rainfall of 334.4mm while Tawau recorded the lowest total rainfall of 148.0mm.

Based on the classification scheme, there were 10 stations recorded very much above average rainfall, 5 stations recorded above average and 11 stations recorded average rainfall. Meanwhile, there were 5 stations recorded below average rainfall and 1 station recorded much below average rainfall.

List of stations in Peninsular Malaysia and Sabah that had registered a new record on the total amount of monthly and daily rainfall for the month of July, shown in a table as below.

The number of rainy days for Peninsula Malaysia ranged from 6 to 21 days while for Sabah and Sarawak ranged from 13 to 23 days.

3. TEMPERATURE

Generally, majority places in the country had lower than average temperature. The mean temperature of the month over lowland areas varied from 25.8°C (Kuala Terengganu) to 27.8°C (Petaling Jaya). Kuala Terengganu recorded the largest negative deviation of -1.5°C from normal.

The mean minimum temperature over lowland areas varied from 22.6°C (Kuala Terengganu) and 24.4°C (Pulau Langkawi). The lowest temperature of the month was 20.1°C being recorded at Kuala Terengganu.

The mean maximum temperature over lowland areas varied from 30.1°C (Kuala Terengganu) to 32.6°C (Muadzam Shah). The highest temperature registered in the month was 35.5°C, in Sri Aman.

Cameron Highlands, a highland station, had temperature ranging from 14.2°C to 24.2°C with a mean temperature of 17.7°C.

4. SOLAR RADIATION

The country generally received lower than average amount of solar radiation. The daily mean values varied from 10.78MJm^-2 at Senai to 19.49MJm^-2 at Kota Bharu. The largest positive and negative deviations from normal were +1.50MJm^-2 and -3.56MJm^-2 at Kota Bharu and Senai respectively.

5 . EVAPORATION

The country had also experienced lower rates of evaporation during this July. The daily mean evaporation rate over the lowland areas ranged from 2.4mm/day (Muadzam Shah) to 4.8mm/day (Kudat and Sandakan). The largest negative deviation was -0.9mm/day (Muadzam Shah) while the largest positive deviation was +0.3mm/day (Chuping and Kudat).

Figures :

Figure 1 : Rainfall Map for Peninsular Malaysia
Figure 2 : Rainfall Map for Sabah and Sarawak

| January | February | March | April | May | June | July | August | September | October | November | December |