Hi, note that TRMM data have 3-hour temporal resolution and simply considering a constant rainfall rate over 3 hours should be enough for hydrological modelling, at least for catchments larger than 100 km^2.

Note also that hourly (or less) rainfall products from remote sensing are also available. See these open access articles for more details:

1) http://onlinelibrary.wiley.com/doi/10.1111/jawr.12140/pdf

Serrat-Capdevila, A., J. B. Valdes, and Z. S. Eugene (2014), Water management applications for satellite precipitation products: Synthesis and

recommendations, J. Am. Water Resour. Assoc., 50(2), 509–525.

2) http://www.nat-hazards-earth-syst-sci.net/13/1959/2013/nhess-13-1959-2013.html

Mugnai, A., Casella, D., Cattani, E., Dietrich, S., Laviola, S., Levizzani, V., Panegrossi, G., Sanò, P., Biron, D., De Leonibus, L., Melfi, D., Rosci, P., Vocino, A., Zauli, F., Puca, S., Rinollo, A., Milani, L., Porcù, F., and Gattari, F.: Precipitation products from the Hydrology SAF. Nat. Hazards Earth Syst. Sci., 13, 1959-1981, 2013

Hi, note that TRMM data have 3-hour temporal resolution and simply considering a constant rainfall rate over 3 hours should be enough for hydrological modelling, at least for catchments larger than 100 km^2.

Note also that hourly (or less) rainfall products from remote sensing are also available. See these open access articles for more details:

1) http://onlinelibrary.wiley.com/doi/10.1111/jawr.12140/pdf

Serrat-Capdevila, A., J. B. Valdes, and Z. S. Eugene (2014), Water management applications for satellite precipitation products: Synthesis and

recommendations, J. Am. Water Resour. Assoc., 50(2), 509–525.

2) http://www.nat-hazards-earth-syst-sci.net/13/1959/2013/nhess-13-1959-2013.html

Mugnai, A., Casella, D., Cattani, E., Dietrich, S., Laviola, S., Levizzani, V., Panegrossi, G., Sanò, P., Biron, D., De Leonibus, L., Melfi, D., Rosci, P., Vocino, A., Zauli, F., Puca, S., Rinollo, A., Milani, L., Porcù, F., and Gattari, F.: Precipitation products from the Hydrology SAF. Nat. Hazards Earth Syst. Sci., 13, 1959-1981, 2013

Many thanks for your comment.