AGROCLIMATIC INFORMATION FOR AGRICULTURAL PLANNING AND OPERATION IN ILOCOS NORTE PARTICULARLY BATAC AND SURROUNDING AREAS FOR THE MONTH OF MAY
I. AGROCLIMATIC SUMMARY::
Partly cloudy to cloudy skies is normal in the area. Total rainfall amount averages 184.7 mm with 9 rainy days. This month usually marks the onset of rainy season. Total evaporation of 183.4 mm are the normal values for the month.
Soil moisture is from dry to moist. Normal relative humidity of 78%. Poor drying condition starts during the later part of May. Leaf wetness duration is from 6 to 12 hours. Daylight duration is 12 hours and 59 minutes with 55% total bright sunshine. This situation gives an amount of 21.4 MJ/m2 of solar radiation during most days of the month. Light southeasterly to easterly winds prevail.
The normal maximum air temperature is 33.6 °C. An extreme temperature of 42.8 °C. was recorded on May 10, 2003. Minimum air temperature is 23.9 with an extreme coolness of 18.5°C. as what was recorded on May 28, 1977.
II. AGROCLIMATIC DATA (AVERAGE)::
| Decade | Rainfall | Rainy | P(TC)* | Tot | AIR TEMPERATURE | RH | Solar | Wind | |
| (10 Day) | (mm) | days | % | evap. | Max. | Min. | (%) | Rad. | Speed |
| (mm) | (°C) | (°C) | MJ/m2 | (kpd) | |||||
| May | |||||||||
| 1-10 | 11.2 | 1 | 7 | 64.4 | 34.4 | 23.6 | 76 | 23.4 | 46.8 |
| 11-20 | 55.0 | 3 | 30 | 58.2 | 34.1 | 23.9 | 77 | 21.4 | 45.0 |
| 21-31 | 118.5 | 5 | 27 | 60.8 | 33.1 | 23.9 | 81 | 19.4 | 47.2 |
* Probability of having a Tropical Cyclone
III. TROPICAL CYCLONE
Northern Luzon which includes Ilocos Norte is within the normal tropical cyclone track. The following are the disturbances over the area (1981-2020).
| TC Name | Year and Date Occurrence | Rainfall Amount (mm) |
| TS Klaring | May 27-29 1986 | 70.2 |
| TS Auring | May 31-June 8, 1995 | 9.8 |
| T Konsing | May 11-17, 1996 | 11.6 |
| TS Ditang | May 20-22, 1996 | 86.0 |
| TD Bining | May 26-27, 1997 | 29.7 |
| TD Biring | May 18-19, 2000 | 22.0 |
| TD Konsing | May 21-22, 2000 | 26.2 |
| TS Crising | May 10-13, 2001 | 88.4 |
| TC Chedeng | May 25-28, 2003 | 145.4 |
| TS Dodong | May 31-June 3, 2003 | 137.2 |
| TY Dindo | May 17-20, 2004 | 23.8 |
| TS Enteng | May 21, 2004 | 18.1 |
| TY Caloy | May 17-18, 2006 | 50.2 |
| TS Cosme | May 16-18, 2008 | 62.8 |
| TS Emong | May 5-7, 2009 | 57.4 |
| TS Bebeng | May 9-10, 2011 | 33.6 |
| TY Chedeng | May 26-27, 2011 | 29.3 |
| TY Dodong | May 9-11, 2015 | 29.0 |
| TS Ambo | May 14-17, 2020 | 18.9 |
TD - Tropical Depression ( >62 kph)
TS - Tropical Storm (62-88 kph)
STS – Severe Tropical Storm (89-117 kph)
TY - Typhoon (118-220 kph)
STY - Super Typhoon (< 222 kph)
