Mosaic Virus
This problem spreads through handling, insects or soil rather than the weather, so there is no live forecast risk — focus on prevention below.
When it strikes
About
Mosaic viruses (Tobacco mosaic, Cucumber mosaic and relatives) infect tomatoes, peppers, cucurbits and many ornamentals, spread by handling, aphids and contaminated tools, with no cure once infected.
Symptoms
Mottled light and dark green or yellow mosaic patterns on leaves, distortion, puckering and stunting; fruit may be mottled, lumpy or fail to set.
Organic Treatment
There is no cure — remove and destroy infected plants to protect the rest. Control aphid vectors and wash hands and tools after handling.
Chemical Treatment
No chemical controls the virus; insecticides only reduce aphid spread.
Prevention
Plant resistant varieties and clean seed, control aphids, disinfect tools, wash hands (especially smokers, for TMV), and remove weeds that host the virus.