From Belmopan...

An interesting weather situation is now developing. There is an upper level low pressure trough as shown by the red line. Next image a tropical wave shown by the black line. The wind shear is relatively low just east of Belize. The tropical wave itself has a fairly large amplitude and actually contains a pair of waves close together. This system should begin to affect Belize late tonight and into tomorrow, Sunday. There could be some locally heavy thundershowers, mainly in the south as seen by the dark orange in the TPW image.