Puna Weather
Sunday 8th March 2026
Today moderate easterly trade winds with widely scattered showers early this morning and only isolated showers this afternoon.
Monday and Tuesday moderate winds out of the southeast with only isolated showers.
Late Tuesday through Sunday very humid with moderate to breezy south winds and occasional heavy rain and thunderstorms. Rain will be more frequent for areas from Hilo south.
Surface high pressure to our northeast is currently driving our trade winds (surface chart). This high will be weakened and pushed east as a mid/upper-level trough that strengthens to our northwest through the upcoming week. The trough pulls deep tropical moisture over us from the southwest late Tuesday through Sunday/Monday with dew points rising into the lower 70s and precipitable water values hovering around 2" (700-300hPa moisture chart). The winds at the surface turn to southerly while the flow aloft is out of the southwest. The southwest flow at the mountain top levels will place windward locations north of Hilo on the dry side. Whereas the southerly flow nearer the surface will enhance rain from Hilo south. There is also colder air aloft which will allow for heavier rain at times and the risk of thunderstorms and mountain top snows.
Currently the greatest rainfall accumulations are likely to be over Kauai and Oahu, but if low level convergence bands set up over our island, we could see flood risk, especially Friday and Saturday.
La Nina conditions are fading, and all models are showing a tendency towards an El Nino state this fall. While the main index region ENSO 3.4 has risen 0.5C over the past four months, sea surface temperatures in our region have risen much more. History has shown that warmer waters to the north of the ENSO region (equator) is often accompanyed by lower shear over the central Pacific. Warmer waters nearby and lower shear could increase tropical storm risk.
It should be noted that there is historical "spring predictability barrier", such that ENSO forecasts made before May have low accuracy.
